[xmonad] question screens

[lg]

Hello guys!

I'm new to Xmond and i like it so far.
Everything works just great expect switching workspaces.

I hope someone can help me.

I'm used to gnome desktop switching so i'd like to switch both screen 
and not just
the screen where my mouse pointer is located.
I't seems like Xmonad is treating every screen as a single screen.

How can i change these settings ? Is it even possible ?

That makes me totally confused.

Thanks for help !

greetings