what is the best tire made for energy saving ? I want the best gas mileage?

Brand and design aren’t going to make alot of difference as far as energy savings. The best thing you can do is ensure your new tires are the size recommended for your vehicle and ensure they are always properly inflated. Installing taller or shorter tires on your vehicle will mess up the gear ratio and almost always decrease fuel economy. There are several more effective ways to increase fuel economy such as installing free-flowing intake and exhaust systems and regular routing maintenance.

The previous answer is just plain wrong and it didn’t answer the question. You want to get a tire with low rolling resistance.
See the link for some recommendations.