Translation:She has a pink horse? Really?
Yes. Questions like "She has a pink horse?" rarely have "không" at the end (E.g: Cô ấy có một con ngựa màu hồng ư? (there isn't "không" here)- She has a pink horse?; Bạn mua cuốn sách ư? - You buy the book?) while questions like "Does she have a pink horse"? do have (Cô ấy có một con ngựa màu hồng không? - Does she have a pink horse?; Bạn có mua cuốn sách không? - Do you buy the book?)
You said about "ư" is very well. It's correct. Now, I wanna distinguish "không", "phải không"/"đúng không"
Không is just use for normally yes-no question
Use use for yes-no question, and when you put "ư" in the last sentence, you was surprised by thing/people.Sometimes we use "á" instead "ư", á is more surprising than "ư".
"Phải không"/"đúng không". We use that when we think we know some things about more than 90% (but maybe it's wrong, it's a kind of subjective opinions), and we wanna confirm it one again.