2 year puppy still not housebroken?

I have a small shih-tzu. He's a great dog, listens to commands but he's still not housebroken. when he was a puppy he use to pee on newspaper but not any more i have tried to lock him up in his cage for 2 weeks and only take him out to use the bathroom but he didnt catch on to it. i bought the housebroken spray on his wee-wee mat and still he wont pee next to it. when we do take him outside he does his business but yet he hasnt learned to hold on till we get outside. I would love for my dog to learn how to hold it til we get outside or if he can pee on the newspaper. any tips on helping me housebreak my dog. i would really appreciate it