I have noticed this issue recently about not being able to go back in time and search for something over say the last 1-10 years. Quite annoying.. Say you put in a trip to Hong Kong a few years ago in your Calendar and then decide to do a search today for Hong Kong in Calendar but for some reason it does not show all the Hong Kong events you created in the past on the iPhone. On my MacBook Pro though it shows them all. They are all synced by the way. If you check manually that date from say 3 years ago after checking date on MacBook you can find it on the iPhone but if you just type in Hong Kong in the search section of Calendar on the iPhone it does not bring all those previous Hong Kong events up.. Why..?