How to find links in the workspace (ctrl + shift + g) in Eclipse PHP?

I use Eclipse PDT, and I opened my project in PHP, autocomplete works, type search works, but that doesn’t work, if I click on the name of the function and press Ctrl+ Shift+ Git will not return other references to this function in the workspace.

I am familiar with Java + Eclipse, and this makes Java look for all the calls to this function in the workspace. I'm new to PHP, so is something wrong? PHP doesn't “reference” things like Java?

(Note: I set the Ctrl+ Shift+ binding Gto search for links in the workspace)