Hi georgy and welcome to YT, congrats on ur new furbabies im sure u are going to have a blast with them!
i have two puppies, one is 5 months and the other is 8,5 weeks, i feed them both royal canin puppy food and im happy with it, they have shiny coats and not greasy at all, there are many brands out there, maybe its best to stick to the same food as the breeder gave them for a while before switching over, puppies undergo a lot of stress when they leave the nest, most people and breeders will advice u to give them the same food until they have settled down in their new home
one last thing, i can assure u that the next best thing to owning a yorkie is owning TWO