Welcome to YT. Would love to meet your girl. Yorkies come in different sizes that's for sure, but they are always called Yorkies, and NOT toy, miniature, standard or tea-cup. T-Pot is just an affectionate name folks here call their babies who weigh 8 or more pounds.
As for the dry skin, she needs Omega 3 in her diet. Dry kibble does not supply the oil they need. There are also other factors that cause dry skin. Winter and heating the house, harsh shampoos, or not rinsing completely.
I hope you find the solution.