Dog vomiting

Question
We have a dog,  she is a mixed breed-mostly German Shepherd, just over a year old. Lately she has been vomiting in the mornings at least a couple of times a week. It is a yellow liquid which doesnt contain any food particles. She is active and eats well. I need to stress that thare are no other sypmtoms and she does not seem to be in any distress, just vomits, gets it over with and happily get right back to her favorite business of terrorizing the cat.  Is it possible that has problem with her food? The vomit looks like bile and I am concerned that she may have gotten into something that has damaged her in some way. She has been known to eat just about anything. Do you have any ideas?  

Answer
Some dogs seem to do that.  My friend had a Lab that threw up if he ate a stick.  If you are leaving the dog in a fenced yard to relieve itself, it is very hard to keep them from eating this and that that disagrees with them.  Besides, plenty to find in the house.

You could ask the vet next time you are in, but I doubt is there is much the vet could do.  

From my housebreaking method:  A couple big putty knives
work well on bowel movements.  Just slide one under it while holding it with
the other.  This gets it up with a minimum of pushing it down into the carpet.
This works with even relatively soft ones, vomit, dirt from over turned house
plants, or anything else from solids to thick liquids.  Finish up with a good
shot of carpet foam.  Note, do not let the puppy lick up the carpet foam.

A Spot Buster also is great.