My Beagle poops at least 10= times a day. At night I get up with her every hour to hour and a hlf. Lately she has been vomiting clear fluids. I feed her puppy Science Diet. I have taken her to the vet and they can't seem to find anything wrong. She is 6 months old and looks like she is 3 months. She really isn't filling out very well. Please help!!!

Optional Information:
Age: <1; Female; Breed: Beagle

Already Tried:
Vet and food alterations