Searching for appointments in a shared calendar

Yeah, I have the same experience. When you type in the search box, it does perform a "filter" operation on the current view, not an actual search. If you have selected multiple calendars, it will "filter" across them all.

If you press the search button after typing the keyword however, an actual search is perfomed, and as far as I can tell only results from your calendar are returned. At least in my tests, no results from shared calendars were included. I will try to get more info on this...