MacOs multiple displays – shortcut to set focus on particular display

I have a Macbook Pro with a cinema display connected to it. I'd like to be able to set focus on the other display by using a keyboard shortcut.

Here's an example of what I mean:

At this very moment I am typing on my second display (external cinema display). But I'd like to open the terminal application on the notebook display by using cmd-spacebar. But cmd-spacebar (and then typing the name of the terminal application) opens terminal application on the external cinema display, which has the focus.

At the moment, in order to be opening the terminal application on the other display, my right hand has to leave the keyboard and either use the trackpad or the mouse and move the mouse pointer to the notebook screen. And only then I can use cmd-spacebar to open the terminal application on the notebook screen.

This interrupts my keyboard oriented workflow.

So, my question is: how can I set the focus to a display via a keyboard shortcut (i.e. not using the mouse/trackpad)?