How to get embedded dog hairs - black ones - out of beige carpet? Vacuum is dumb. It's a red Hoover one.?

I don't know to make the attachments work right. The suction is awful. Any tricks? It also spits carpet wads all over the place. What's wrong with it. It's not mine; I clean for someone so it's all i got. It's supposed to be really "nice" and expensive.