As far as what product, dog food only. You can compare labels - any 2 vets will likely have 2 different ideas as to the best dogfood. But no dog should be fed human food, for several reasons. Just look at the labels and buy the food that best matches your pet's age and any special conditions. If you wish, call your local vet and ask what dog food they use there.
If you want to know more about feeding, including when, how often, how much, etc, try this website:
http://www.all-about-yorkshire-terriers.com/nutrition.html
Science Diet
I work in a veterinary clinic and the makers of Hill's Science diet partner up with the vets and tell them to "recommend" their dog food. Even though the dog food is a better food than most, it's not the best food out their.
where is a place that has the most vets
Some vets are but most are not.
Yorkshire Terriers should not shed fur (as far as I'm concerned, because my families Yorkie doesn't shed fur). So it could be a bit bad, especially if it is winter as it could get cold. I would recommend taking it to the vets so they can tell you what is wrong with your dog.
There are many, the worst is considered heart worms, and most vets recommend that all dogs get treated for them, I think twice a year.
Most vets recommend boosters every 3-4 weeks until pups are four months old.
There are some great dog foods on the market. Most vets suggest Iams brand, Pedigree, Science Hill Diet or Beneful. They are all very good for your dog.
You should feed the rabbit more hay and dried foods, and if this doesn't work visit the vets.
Nipping or chewing the leg can cause swelling for a dog i recommend going to the vets
You cannot get the answer from the internet, you can but I would recommend special info from real vets.
most likely pets and pet owners