Command + f hangs Finder I just bought a new MacBook Pro running OS X 10.10.3 and then migrated from my old Mavericks MacBook Pro. Now when I search for a file using command+F, Finder hangs/beachballs/becomes unresponsive after just a few letters. Here's what I tried and what happened:


Removing com.apple.finder.plist or com.apple.dock.plist from /Users/username/Library/Preferences then rebooting (as suggested various places such as here) didn't fix the problem. 
Trashing the contents of Library/Saved Application State/ then rebooting did fix the problem—for exactly one search, subsequent searches had the same problem as before. I deduce that the saved state might be a part of the problem.  
Restricting the search to PDF or Document before I type search terms also fixes the problem, from which I think that the size of the set of files to be searched might be a part of the problem.


What is causing this situation and how can I fix it?
Based upon your descriptions, it appears to be an active bug related to smart search and regular search.

On page two of that discussion, one of the posters stated the following:


  Here is what finally fixed for me. I went in mail.app (whose search
  was totally misbehaving too), and I rebuild all the mailboxes in my
  accounts. (Select all the folders, "Folder" menu, "rebuild") When this
  finished, I rebuilt my index again, restarted and... it is working
  like a charm since then!