"Xkb Options" Dialog and keyboard layout swithing

Hi ! I defined two keyboard layouts in fresh installed TDE under Debian Stable (jessie): one for Finnish and one for Russian keyboard. I did it via "Trinity Control Center --> Regional and accessibility --> Keyboard Layout --> Layout". So now I can switch the keyboard by clicking the ru/fi flag symbol in the panel. How can I define a keyboard shortcut to switch it? On some old machines with TDE I somehow managed it, but now I just can't. Whatever I click in the "Switching Options" or "Xkb Options" --- nothing works, the only way to switch keyboard is the mouse click. Please explain, how I can do it just by TDE configuration. Thanks! Ilya D.