I hope your dogs will soon have some relief from the vomiting episodes you describe.
If your dogs are suffering from gastrointestinal illness as severe as you describe, it is definitely merited that you pursue a veterinary examination.
With vomiting, is important to not put any further material into the stomach, so hold off on providing any food or water until the vomiting subsides for at least four hours. At that point, you can give them ice cubes to lick or small amounts of room temperature water or unflavored Pedialyte.
PHOTO: a w ferguson