I get the curiosity — I've searched for this kind of thing before myself when a name sticks in my head from a documentary or old article. If you mean Beth Thomas from the 1992 documentary 'Child of Rage', the best move is to be methodical: try Google with quotes around the full name plus context keywords like the documentary title, year, or any known locations. Reverse image search can help if you have an older photo to compare, and try variations of her name (maiden vs. married, middle name, initials).
Expect noise: Beth Thomas is a common name, so lots of unrelated profiles will pop up. I always cross-check small details — age range, location tags, interview clips, or family names mentioned in articles — before assuming a profile belongs to the person I’m looking for. Also check news archives, YouTube interviews, and the documentary’s production credits; sometimes producers or interviewers post updates where the participant is mentioned.
Lastly, be gentle about privacy. If she’s chosen not to be publicly visible or uses a different name, that’s a choice I respect. If you’re trying to reconnect for positive reasons, consider contacting the documentary producers or using public records that respect privacy laws rather than digging into private social accounts.