My two Yorkies and My Maltese look like Chihuahua's when wet. That doesn't mean they are mixes (although one of them IS a mix, not with a chihuahua though)
It's like when you take a bath, you look a little different when your hair is wet. Or for example, when a girl wears make-up and she washes it off, some girls look really different..
but good for you to ask questions because I agree with you, if you don't ask you won't learn.. We were all newbies @ one point. I still am even though I've almost had my first Yorkie for a year now. I'm still learning about them.