My 8 weeks old lab love to eat small stones and papers.what is the most suitable solution for this problem
Of course eating rocks, sticks, mulch is what young lab pups will do. It's not good. They will get over it but in the meantime practice deny, deter, distract. If not, you will end up with some expensive surgery bills.
Puppies all do this but yes you want to try to prevent your puppy chewing inappropriate things, especially stones. I would always stay in the garden with a young puppy so if he picks up something he shouldn't you can swap it for something else - a food treat or a toy. If he doesn't want to give it up you can become very exciting with what you have to offer.
Ours did this relentlessly. We swapped the stone for a treat (piece of kibble) saying drop and now at 15 weeks he will still pick them up occasionally but always drops on command.