I can search for a specific term and a few scrolls later I'll get videos I previously watched or liked as search results, which never have any relevance to the term I entered.
This is deliberate. It's probably for the same reasons why comments are arbitrarily sorted and why live chat always sorts by "Top" rather than "Newest" (whatever "Top" even means to YouTube, idk)
I think search includes words mentioned within the video and comments. Often prioritising this over a title and description. This leads to bad results finding things.