...or try boiling some chicken and cutting it up finely and mixing it with the kibble (dry dog food). I had to experiment for awhile to see what dry food mine would eat. Just be sure it is a good quality food.
If it's not too hot or too cold, I think yorkies can outwalk us!
When it gets cold, though, remember that your yorkie doesn't have but a single coat of hair and will need a sweater or coat to keep warm.