Search for duplicate code in certain folders

Hello!

I have a project that was created with the Zend Framework.
For this project classes were created in different folders.

For example:

/ application / modules / front / controllers /
/ application / modules / front / models /
/ library / tools /

I want to look in those folders to duplicate code.
How can I 'Code' -> 'duplicates locate' a search in these folders perform ?

Is there a way to highlight script code and perform a search for duplicate code?

Sincerely yours

Stephan