Use bluetooth keyboard with a different layout? I'm Italian, so I use italian language on my tablet (note 10.1), but I have also a bluetooth keyboard with english layout that I use to write little snippets of programmes, the problem is that I don't know how to set english language only for the keyboard. Can someone help me to solve this problem?
You need to install physical keyboard layouts.
One of the best extensions to do that is this:

RS - Hardware Keyboard Layouts

It is free, and does nothing else. You use the standard settings page to select the hardware keyboard layout.

(It is mystery why Google does not provide the layout files by default.)