How to use EasyFind (or a similar application) to search inside ~/Library?
The simplest way is to just tell EasyFind to search the entire drive for invisibles.

It's not very efficient, but it's very easy.

Alternatively, it will search any folder you drag to the 'location' drop menu.  

For a folder which is normally hidden, such as ~/Library, there are several methods to reveal it.


Finder > Go Menu - hold  Opt ⌥  &amp; the User Library will be revealed in the menu
 From comments, this may be yet another of those commands that changes by System Language. Adding Shift may apparently be necessary in some languages.
Use the Go To Folder... command from the Go Menu or  Cmd ⌘   Shift ⇧   G   &amp; type ~/Library
You can always go to any invisible folder this way, however deeply it's nested, for instance ~/Library/Application Support/Anki2/. Note it doesn't need the space escaping.
Permanently unhide by going to Finder,  Cmd ⌘   N  for new window;  Cmd ⌘   Shift ⇧   H  to go to Home folder;  Cmd ⌘   J  for View Options, then check the Show Library Folder box.
Permanently unhide using Terminal &amp; the command
chflags nohidden ~/Library
Revert with hidden
Unhide all hidden files &amp; folders using Terminal &amp;
defaults write com.apple.Finder AppleShowAllFiles TRUE;killall Finder
Revert using FALSE