Parvo is a viral infection of dogs and most dogs that get their vaccines are protected from it by their shots. Its seen mostly in very young or unvaccinated dogs. You can read about parvovirus here
The yellow your dog is throwing up is probably stomach bile.
Dogs throw up for lots of reasons including illness, eating a non food item, overly rich food, spoiled food, intestinal parasites, chewing on toxic plants etc.
You may want to see your vet with your dog to see what exactly is wrong.
If you can't do that then you can see if the dog can hold down plain pedialyte for fluids.
You can try an over the counter med such as Pepcid or Tagamet.
Be sure to tell the vet when you see them if you use either of these.
You can read about dose amounts (and cautions) scrolling down on the pages here
You can also see if bland food will help your pet feel better.
I would suggest trying boiled chicken meat or hamburger with the fat drained off, mixed with really well cooked rice in a ratio of 1/3 meat to 2/3 rice to see if that works. It’s not a balanced diet but OK to use for a few meals while working on controlling digestive upset.
But if the dog cannot hold down anything its in danger of becoming dehydrated and needs vet care for that along with finding out what is causing the problem.
Hope this helps you!