The navigation manual has quite a few navigation commands, but not all of the generic car commands.
For example, saying "Navigation" (or "Map") will bring up the map from the home screen. Saying "Media" will start the sounds of nature. "Radio" will start the radio without changing the station.
I don't see those mentioned in the manual, and found out about them simply by trying to say voice commands for the buttons in the car.
(For reference, the manual is attached below, voice commands start on 6-8)
Edit: I can't upload the manual, the file is too large, but if you log into kia's website or check your paper manual you'll see it.