Yorkies love to love their people. They are their persons shadow, and unfortunately that makes it so that they're not the dog for everyone. I'm not saying that's the case for you. One thing you should try is training. Start with simple obedience. That will make a big difference with your little one. You have to teach them what is right and wrong, almost like a little kid. What you would consider acceptable behavior, and what isn't.
My boy doesn't like having people over at my house. He occasionally growls at visitors, especially the people he doesn't know. He is so well trained, all I need is the correction I taught him and he backs off, just like that. He doesn't necessarily like it, but he knows it's not something I would allow.
__________________ Littlest JakJak 
We miss you Kaji 
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