Feeding human food is great for them but feeding leftover scraps is not.
I homecook for Ellie and she LOVES it.
You could feed her boiled white meat chicken with no seasonings, apple bits (no skin), melon, squash, carrot, sweet potato, potato, berries, lettuce, rice, banana... If you homecook, you will have to use supplements though. If you just want to mix a small amount into her kibble you would avoid the need to supplement and she might eat it if you find a food she really likes.
Dogs won't starve themselves if you leave food down but my opinion is that my dog should like what she is eating. As long as I can get something healthy into her (no problem for me thankfully), she should get what she likes within reason. Also with Yorkies you have to be careful because at least one Yorkie I know of held off on eating and threw up bile and it would be so easy for your pup to go into hypoglycemia this way.
