Oh please!
I want to find 3 things:
UI
HUD
RTS
Am I doomed? =_= Search Engine won’t let me find what I want 
That happens, those letter combinations can be found in various words and would result in a large number of results which slows down the server and that’s why they aren’t allowed in search.
https://docs.unrealengine.com/latest/INT/Search/index.html
It looks like the search here will accept UI, HUD, and RTS. It’ll search everywhere, but you can also filter to only forum results if you’d like. 
Hope this helps!
Oh, splendid!
Thank you very much!