1) Ya-hoow is a 'cool' way of saying Yahoo a noise commonly made when cheering, often after jumping off something
2) Ya-hoow is also a 'cool' way of referring to the search engine known in English as Yahoo.
Person jumping off a diving board: "Ya-hoow!!!!"
Tom: "Hey Becca, do you know any good restaurants?"
Becca: "Nah, just see what Ya-hoow says"