Why don't Return or Enter keys start a search in X7?

In X4, when I typed into a search field and hit Enter or Return on my Apple keyboard, it would start a search. In X7, I hit Enter or Return and nothing happens (OS X 10.9). How do I bring back the old behavior - I don’t want to have to move my hand to the mouse off the keyboard each time to click on the Search; what button can I press to have it start the search?

Greetings Melvin,

So far, I’ve been unable to reproduce the situation you’ve described with EndNote X7 on my Mac.  Just to confirm, which search field are you typing into when return doesn’t initiate the search?  Is this the Quick Search field toward the top right of the library window, or the main search panel you’d see by clicking “Tools>Search Library…”?  Have you updated your EndNote X7 to version X7.4? 

Please let me know what you find.

It was the main search panel. Someone from Endnote tech support suggested I delete some preference files, which seems to have fixed the issue.