Get hard rubber toys that are meant for avid chewers, like a Kong (they make really tiny ones for little dogs). These types of toys stand up to my pit bull who LOVES to chew--they generally last 6 months which is more than any other toy ever has. He destroys everything else I give him. You can stuff the kong toy with peanut butter and freeze it, and that will keep your pup busy for a while. You can also get treat-dispensing rubber toys (Planet Dog is a good brand) and put some kibble or treats in it so your dog has to work at it for a while to get them out.