Because it's not semantic search, it's text search. You don't search Discord like you search Google, which is a problem when it is used as a wiki replacement.

Discord's text search is a simple intersection-of-all-words search, with some filters slapped on top. And it's not even the word you typed, it's all words that seem maybe semantically equivalent or similar. When I know the exact word I want to search for (e.g. "loves"), it sucks to always get results for every other related word (e.g. "love", "loved", "loving"). Maybe it'd be a useful feature if it had a toggle, but it doesn't. Some other words that have problems with this are time/times, caring/care, wanting/want/wants, and fucking allowance/allow/allows. Seriously?? Allowance is treated the same as allow??

Can't search for or with symbols. Lots of search engines have this issue. Just ignores them. Want to search for instances of ":3"? You're actually searching for instances of "3". Not much else to say on this other than it's annoying.