How to find someone on Facebook
Facebook used to have the best people search on the internet. Graph Search let you ask questions like "people who work at X and live in Y", and it was dismantled precisely because it worked too well. What is left is thinner, but it is not nothing.
1. Face search, because names are optional
Public Facebook profile photos are reachable from the open web. A face search can hand you a profile even when the account uses a nickname, a maiden name, or a name written in another alphabet, which is the single most common reason manual searching fails.
2. Search the name with one anchor
Facebook's own search is still usable if you give it something to narrow on. Search the name, then use the People filter and set a city, a workplace, a school or a mutual friend. One anchor removes most of the noise; two removes almost all of it.
3. Go through the mutual friend
The friend list of one person you can find is the most productive route on Facebook by a wide margin. Even where a friend list is hidden, people tag each other, comment on each other, and appear in the same event photos.
4. Search the site from outside
site:facebook.com "Marek Tolvaj" Tallinn
Public profile pages carry the name in the title. Google and Bing index them, and their exact-phrase matching is better than Facebook's own.
5. Try the other properties
Instagram and Threads accounts are frequently linked to the same person, and Messenger profiles are reachable when the Facebook profile is locked down. Marketplace listings expose a seller profile that is otherwise hard to reach.
6. Groups and events
A person invisible in general search is often visible inside a public group they post in, a local buy-and-sell group, a hobby group, a neighbourhood page. Group member lists remain browsable in many cases where the profile itself is not.
What is off limits
A locked profile is a decision, and there is no legitimate way past it. Tools promising to show private Facebook photos are, without exception, scams or malware. What remains public even on a locked profile is the name, the profile photo, the cover photo and often the city, which is generally enough to confirm identity.
Judging what you find
Facebook accounts age well as evidence: a profile with a decade of birthday posts from people who clearly know the person is very hard to fabricate. A profile created this year with forty friends and no photos of anyone else is not evidence of anything.