Funny....
One of my dogs would "show me". One night as I slept Duchess hit my hand with her nose, I asked what she wanted. She went to the door to be let out. She went out and did her business. I let her back in and went to sleep.
Some time later she tapped my hand again. She went to water bowl it was empty. I got up, filled it, set it down and then went back to bed.
Just as I was dropping off to sleep she nudged my hand again, I looked at her and said now what do you want ? She stared at me and then took a step closer and burped right in my face. I guess that was her way of thanking me for the water.