Welcome to Yorkie Talk! Can't wait to see pictures of your Yorkies and hear all about them. You were so lucky to have had 2 to age 15, and now starting over must be fun too. I think having pairs of them is the greatest (so much so that I have kinda 2 pairs, haha)
Here is a website for Minksheen (which by the way I use and love for all 5 dogs)
MinkSheen Pet Shampoo -
There are many foods of higher quality than Science Diet, and here is a link to the Health and Diet section since you are new to the site and may not have seen it yet:
Yorkie Health & Diet - YorkieTalk.com Forums - Yorkshire Terrier Community