Recently bought a Mac for the first time and changed from Google Calendar to iCloud. Have now just found that I can't search my past events, which I need to do for billing purposes. (I have lots of weekly repeating engagements.) Think I will have to go back to Google Calendar since the web interface lets you search past events quite easily. All very efficient and as it should be.
Have reported the problem at http://www.apple.com/feedback/ but note that there is no feedback for Calendar, only for iCal which only goes up to version 4.0.4 so I used the OS X feedback option. I am using Calendar running on OS X 10.8.2 and it says that it is version 6.0 (1645).