Vibration by car Hyundai Elantra 2005

I have vibration that has increased in the last months when I place it in D. When speed is increased on road as a silk, or just when I am in the semiàphoro that I put it in neutral and feel much less the vibration, they told me change of motor supports and box and service to acceleration block, cables, new spark plugs, injection service, slightly improved. What can it be? Thank you