Question

when you push a heavy object it does not move explain the reason in terms of net force​

Answer 1

because opposite force is being applied by the ground known as static friction

Answer 2

If there were no friction or any other opposing force an object would definitely accelerate if a force is applied however small it may be.The reason that an object does not move on application of force is that static friction balances the external force that we apply on the object.If you push a box horizontally , friction from the ground acts that is exactly equal to your force but acts in opposite direction on the object.If you push the box forward the friction from the ground acts on the box backwards and the interesting fact is this static friction adjusts itself according to your force .If you increase your force then static friction also increases itself but upto a limit.Once you cross that limit the object starts moving, there after it can no longer increase .Infact during motion friction is slightly less than what it took to start the motion!Hence neither force goes anywhere nor does inertia balance force .Hope this helps you