Been a long-running issue since I started the game. Searching by alliance acronym or the full name usually gets me random matches even if I typed the full alliance name or acronym.
Also they could do well to actually give alliance recommendations that are in you power range for better fit. The default listings even when I first started out were full of junk alliances that almost nobody would ever join with only the occasional 5 millionish alliance after you refresh a dozen times to frustrate the heck out of you. I wind up having to search event leaderboards for stronger alliances or see my friends’ alliances which defeats the whole purpose of the alliance search feature.