I have my little girl Miley, she is an 8 month old Boston Terrier. She throws up all the time!!! She eats and throws it up..this can't be normal. I have taken her to the vet and the vet gave me laxitive to give her saying she has ingested something and it was plugging her up. Well that can't be it, she is still have normal bowel movements. We switched her to a different food (PMI Exclusive Puppy Chow) and she did better for a bit but now it's happening again....can anyone provide me with more guidance??

 Thank you~