You have it spelled right now - SHIH TZU.
I have one. My biggest advice? Be very patient

They are very difficult to housetrain, very stubborn, and not one of the brightest breeds. However, they make up for that in their undying love and affection, being a cuddle bug, and being happy to just be with you.
Harley is MY baby - I love him to pieces. But he has not been easy like our younger dog. Actually, getting our younger dog potty trained Harley about 95%. He still has accidents and probably always will unfortunately. We have to keep a constant eye on him. He only knows 2 commands even after hours and hours of working. I have a feeling he knows more than he's letting on but is choosing not to listen

Our other dog, on the other hand, knows TONS of commands and tricks.
But Harley does his job well. They were bred for royalty and to sit on pillows and be pamped. He does that well! He does not think of himself as a dog, he's much too good for that, and he's a great companion. We adore him
