This is also why we don't have "quote-boost" like twitter or tumblr have. It's very controversial and earlier on it was a pretty even divide of users who wanted it and users who had arguments that having it would promote harassment and abusive behavior. It's not that it's some official verdict that it'll never happen if ppl _really_ want it but it was deemed unimportant/low-priority.
personally i think quote-boost is bad and should not happen for many reasons.
In case anyone is wondering why you can only search hashtags, this was, to a lot of us, a beneficial design decision to counter-act harassment, so that nobody can just do a search for "otherkin" or "intersectionality" and then find all the ppl they want to harass, etc. etc.
it wasn't a hard-set thing and has never been fixed in stone so it may be changing but if you're making requests for "real search" do consider the ramifications for that.