While training her Yorkie my mom decided to take away the meat she had offered him after he put the meat in his mouth. My mom said 'leave!' to the Yorkie. She didn't mean to be cruel, but rather wanted to remind the dog where he got his livelihood, and to respect the food that was my mother's.
If a Yorkie knows the people approaching your house for a visit they may welcome the guests if the guests are visible. However, if the guests are approaching a shut door as in most cases the Yorkies will bark protectively to alarm of danger.
A friend of mine taught her dog, by these means, never to eat a rabbit bone. She takes all the bones she can see out of the rabbit she has, but missed an occasional one.
My mom had a Great Dane that chewed everything, and she wasn't very happy about this fact. My mom did was she had to fetch a piece of meat and the dog promptly snatched some. Mom took it away, and just as the animal was going to seize it she said 'leave' in a thunderous tone. Surprisingly, this dog sat back, astonished, and mom offered it the meat again, and repeated 'leave!' in an ordinary tone; the dog did not attempt to touch it.
Another friend's Yorkie sneaks food that drops on the floor at dinner time. This Yorkie sometimes whimpers for scraps of the owner's meal. Avoid if at all possible feeding your Yorkie table scraps, as Yorkie's stomachs are sensitive. I would rather resist a dog's whining and begging for scraps than pay a hefty veterinarian bill!
Yorkies could be seen as greedy by some. Yorkies should be taught good table manners. "Spoiled" yorkies' behavior can easily be corrected with the proper trainer discipline. The most difficult part of training is not getting the dog to respond to training methods. Instead, it is more difficult to stick to the plan as the trainer!