We have all been there. There is a movie you watched many years ago, possibly in your youth, that lives on the edges of your brain, always eluding your attempts to grasp it and pinpoint its exact name. Don't worry, all might not be lost. If you follow these methods, you're very likely to finally track it down. But first, an effort is needed: you need information! All you can get! The more you remember about the movie in question, the greater your chances of finding it.
As I said, before starting to use the methods to search for that movie you can't remember, you should gather as much information as possible. Every scrap of memory helps. The more coherent and precise, the better. Think hard: What year is your movie roughly from? What genre? Do you remember any actor in it? Can you hear any snippet of the soundtrack? Do you recognize a song? Can you describe, even briefly, a fragment of any scene? THINK! Write down everything you remember somewhere and then start using the methods below. They go from the simplest to the more complicated and cumbersome. If one doesn't work, move on to the next.
"Method of the Actors"
Let's start with the simplest method, if you meet the main requirement: remembering the name of one of the actors in the movie. If so, you just need to visit the artist's page on IMDB or Wikipedia to find the complete list of films they have appeared in. Go through the list until you find the movie you're looking for. Easy as one, two, three!
Method of the Music
Similar to the Method of the Actors, but with songs. If you remember a song that appeared in the movie, or even just the band that performed it, there's a good chance you'll find it with a simple search. For an easy example, if you search for "Aerosmith Movie" without quotes, the answer to your question will already appear among the first results. Armageddon!
"What is My Movie method"
What is my Movie is a site that serves exactly to resolve this kind of doubt. In other words, to know the name of a movie you can't remember. It uses a special algorithm and indexes movie sites specifically, so it saves you from Google's junk results. It requires you to ask, in English, about the movie you're looking for with the details you remember. In my experience, it only works if the movie is at least somewhat known, but you can give it a chance before moving to the next method, where we start using somewhat more cumbersome solutions. The site is What is my Movie.
"Method of the Lists"
If you still can't find the movie, the best thing is to resort to lists created by the endless websites and YouTube compilation videos. For example, if you're sure the movie you're looking for has vampires, the search would be something like: Movies about vampires (yes, IN ENGLISH, because there's much more accurate information in that language, if you don't know English use Google Translate). This way, you'll usually get a bunch of lists with several similar movies, and you just have to visit each one and see if the one you're looking for appears on any of those pages. Generally, sites like Ranker, Wikipedia, and IMDB user lists tend to have the most relevant titles, so start with those. You have nothing to lose by trying!
"Method of the Loose Words"
This method proves useful as a last resort and works when you only remember scattered details about the movie. Again, we'll use Google to try to uncover the mystery. In my case, I always use the few fragments I have in my memory and type them IN ENGLISH. For example: Movie witch children mouse comedy. Loose little words that, if you google them right now, will tell you the movie I'm referring to.
Sometimes you might get a movie that isn't the one you're looking for, but the details you remember still hold true. Then just use the minus sign (-) to remove that movie from the results and refine the search. For example, using the previous case (and if the movie isn't "The Witches"): Movie witch children mouse comedy -"The Witches". The more loose memories you add, the more you'll refine the search, though sometimes they can also work against you. The best is to experiment, adding some, removing others, etc. Or maybe you'll have better results if you search movie about witch who turn children into mouse, weaving a more coherent search, it depends. At this point, everything is trial and error.
"Method of the IMDB Keywords"
Well, when all of the above fails, it's time to get serious and resort to one of the most useful (and hidden) tools in the Internet Movie Database: the movie search by keyword combination. It's a very powerful search engine that works by grouping "tags". Similar to the loose words method, but with predefined words that get grouped as you select them, helping IMDB to find the movie you're looking for.
The best part is that, besides the tags, it allows you to refine the search with other parameters such as movie genre, time period in which you think it might have come out, the score it might have, whether it went straight to TV or was released in theaters, and other similar things. The tags are also quite specific, for example: twist ending, post-credits scene, casual sex, people smoking tobacco, and hundreds more like that, all on point. Undoubtedly, a crucial tool for finding the name of that movie you can't remember.
"Method of Social Networks"
Collective intelligence at your service! If you have Facebook, look for a group related to the film genre of the movie you're looking for. You'll find groups for every taste: horror, comedy, science fiction, action, etc. Possibly dozens of results will appear, so it's better to subscribe only to those with the most members. Once inside the group, ask your question about the movie you can't remember, providing as many details as possible. Genre, year, characters, actions, any scene you remember, etc. Be as descriptive as possible, and as polite as you can. In these groups, there are many people (like yours truly) who enjoy solving these mysteries and will put themselves at your service. That said, in my case, I only do it if the person asks politely and shows genuine interest, answering any questions they're asked and following the conversations that may arise from their query. Nobody likes wasting time on ingrates.
"Method of Leaving a Comment on NeoTeo"
If all that fails, well... you can use the comments on this article and I'll try to help you. My specialties are horror cinema, science fiction, and fantasy, but I also do well with comedies and action movies. Of dramatic or historical cinema, almost nothing. Use this option only if you've tried all the previous ones and they haven't worked, and follow the same etiquette I describe in the Method of Social Networks. If you don't, consider your comment ignored.
Conclusion
Personally, following these methods, I manage to find the names of the countless movies I've seen but can't remember in 90% of cases. There are always obscure films, almost unknown, that someone watched by chance, that remain elusive and resist the steps mentioned here. Fortunately, that wasn't the case that inspired me to share my search process: I happened to remember watching a movie about a bald kid who used a potion to make his hair grow, but whose name I couldn't pin down. Using the "Method of the Loose Words", I found the film in a couple of attempts. Look what movie it was!