unfortunately it really is a middle/back end problem that you can't just magic up a search button...

this is my specialisation, after all, not that i have actually built a full text search engine, i rewrote fiatjaf's filter search system so it was more readable

nostr filters are all you get as a guarantee, there is some nip for search functionality, the hipster in crowd nostriches like to call them "DVM" and nostr.band is one of the search capable relays i think