[B-Con]

That's a good point.

It was missing from my list because I honestly never use G+ search and didn't know how to best assess it.

[dredmorbius]

I was pretty gobsmacked when it showed up missing.

For a while there, before Google's "you will be assimilated* policy really showed itself, Search was about the best thing about G+. I've since abandoned it largely for Reddit, which does have a featureful search, though it's not comprehensive (comments aren't indexed).