Would anyone else want to see a search option that allowed you to show the most recent answers? By doing so you could do
answers:0, mostrecent:YES [whatever other tag]. Or is there already a way?
Currently, you cannot search for answers in this way. The best you can do is search for questions and then sort by the most recent activity (the "active" tab).
I don't think what you're proposing makes a lot of sense because searching for answers by recent activity would give results fragmented across topics. I have a difficult time imagining a use case for that.