Currently beorg simple searches don't support OR (i.e. has tag Fred OR has tag George). You can write more complex searches in Scheme, for example:
(and (or (member "fred" (item-tags item)) (member "george" (item-tags item))) (member (item-state item) '("TODO" "WAITING")))
I haven't tried this, but the above should work. I hope at some point to make the simple (non-Scheme) search be able to handle the scenario you've described.
There is an introduction page to scripting in beorg at https://www.beorg.app/manual/scripting/
Under the hood beorg uses BiwaScheme - https://www.biwascheme.org/
Gahallgrimson