A food that is generally accepted by dogs and is easy for them to digest is a mixture of white rice and chicken breast meat. The cooked chicken can also be given by itself. See your vet if your dog shows no interest in any food for more than a day or two.
Normally when you change up your dogs food to something different they like it more. Sometimes i mix canned food with my dogs dry food and she likes it more. I also used to make scrambled eggs for my elderly dog because she would not eat her regular dog food.
It can be said that dogs are made to walk or run. So the first thing that should be tried is to exercise the dog. Take the dog for a run. It is important that the dog run "forward" and not just in circles. An exercised dog will be hungry.
If your dog is not eating any of there own food and not getting table scraps or being feed some were else then there is some form of a medical problem going on. In that case your dog needs to see a vet as soon as possible to find out what is wrong .