Have u tried to put peanut butter in his Kongs? That works for me with my dog. Also, we've found that real tennis balls last longer than dog-store tennis balls (100x longer). We also like to give her ''mastadon'' bones from Wal-Mart (between $8 & $9), which r the huge bones that take forever to eat. Knuckles r good, too, & r usually less expensive. My dog is favorite chew toy is a hoofie, a cow is foot. They smell nasty, but that is why she loves them. They r only 99 cents & last a long time. But they smell, so some of these r better for the outdoors or basements or kennels. We also love floss ropes, ropes with real dental floss in the rope. She loves tug of war, & this way it is good for her teeth.
My dog loves destroying soft dog toys, too, & I have stopped buying them except for once in awhile I will spend a dollar for a few minutes of her destructive entertainment. but no more than a dollar for a soft toy.
Peanut butter + kong = dog occupied for hours