In the past month I've had to use Discord search to find something important twice. Both times it took 20+ minutes and when I actually found the results I noticed that I typed things that ought to have given me the results but just didn't. In one other case I never actually found the correct message but found the URL I was looking for elsewhere and decided to try it out to see if it'd find the correct message. Pasting literally the exact URL did point to the correct message but no other combination of host, part of URL, etc. would.

While that's not technically unusable it's far beyond the level where I'll even try to find something in Discord unless it's very important.