Your English seems good to me, don't worry about that.
And now I do understand what you want.
) I believe the solution you want,
if it is possible, will be attained by playing around with those settings in Control Center. I do not know for 100% certain if that exact setup is possible with KDE, but I would like to think it IS, because there are many combinations of settings in the Control Panel.
Until someone comes in here and maybe tells you EXACTLY how to do it, you may just find it by toying with the settings. I have noticed that some settings do not act exactly as I would have guessed they would, and took a lot of toying around to get it how I liked it. You may just need to do the same thing.
Sounds like you kind of need focus on TWO windows.. Hmm..