Before commenting on this thread I read the OP's previous thread for more info:
http://www.yorkietalk.com/forums/yor...-question.html
Based on info given in both threads my comments are:
1.
Don't force feed a 7lb. 5 year old dog. You may think that the throwing up bile is caused from not eating, but I would be more inclined to think that the not eating is the dogs way of backing off food because something is upsetting his system. The throwing up bile may be due to whatever underlying problem is there.
In your previous thread you said you had blood work done, but I don't think you had a bile acid test done. I think you should do it, as it would help you see if your dog's liver is properly handling food/fats/protein etc.
My Tiki has times when she backs off of eating and has yellow vomit and diarrhea. She has MVD, which means her liver does not properly filter toxins. She does very well if I make sure she eats only a high quality kibble that is lower in protein and fat; but if somebody gives her a piece of bacon or cheeseburger.... she gets sick.
I'm wondering if maybe your dog might have the same problem. A bile acid test would give you more information on how he processes food.