YouTube search went to absolute trash, same as Gmail, same as Google the search engine.
Many time I search for a video I know the title of, letter by letter, in quotes, and it does not show up (at least in the first 50 or so results). Sometimes I think the video might have been deleted, only to find it out later in my bookmarks and realizing this is not the case.
Crazy how them being fundamental to what we all know as "the web" nowadays, allows them to get away with being extremely mediocre and oblivious to user's needs.
I am forced to use Yandex just to find stuff Google or DDG never shows anymore.
I often find that using Google Search (the Video tab, with "site:youtube.com") allows me to find videos that don't show up in the YouTube search... or sometimes vice versa!