I was wondering if there is a way of doing this and how.
I don't believe searching propositional outline labels is possible at the moment. I have seen at least one request for it but don't believe I have seen any comment from Faithlife.
Sure would be nice.
At one point Sean did say on the forums it was something they plan to add in the future.
[Y]
It's not currently possible, but we know there's significant interest, so it's on our (very long) list of things to add.
Anything like it in the many resources or search possibilities?
Lexham High Definition New Testament comes closest. You should be able to right click a 'label' and get search suggestions.
