A Shih Tzu needs activity, interaction and a daily schedule that keeps them busy in order to be well adjusted and happy. If a dog is left alone to their own devices and it is believed that they will stay content by simply laying around the home, this is a huge misconception!
A Shih Tzu can display destructive chewing if they are not given enough stimulation. An owner must keep a daily schedule of exercise, feeding, play time, grooming and interaction. There will, of course, be many times when an owner is otherwise busy. It is those times that a dog must be shown what is appropriate chewing.
It is best to rotate dog toys. A dog will become bored seeing the same toys all of the time. 1/2 of the toys should be tucked away and 1/2 should be left out for the dog. After a week or so, they should be switched.
Dogs are most content when given toys that produce results. Toys that make noise are a good choice. Toys that produce a treat for the dog are best, especially when a dog is left alone and really needs dog toys that keep them occupied for long periods.
When a dog chews on something inappropriate, an owner should immediately stop the action, give a command, offer a replacement and give praise for appropriate behavior. For example, if your Shih Tzu begins to chew on the leg of your coffee table: Walk over to your dog and stop them from chewing, say a firm and strong "No!" and then give your dog one of their toys, offer an abundance of praise for chewing on their dog toy.
To stop destructive chewing, in the beginning phases of training, a huge display of praise should be given, as if your dog just did the most wonderful action in the world. After several weeks, the Shih Tzu will understand which actions cause disappointment in their owner and which actions make their owner happy. Dogs have a natural instinct to please. By training your dog in this way, you are helping them to behave in a way that makes both owner and Shih Tzu happier.