Though it is possible to find them , it is very difficult. Clear lenses blend in with water. The best way is to heat the pool water and make all the water steam away, then you will find your contact lenses. Personally I think it's unnecessary to get them back because even if you find it back, you cannot use it anymore. The water in the pool is usually full of bacteria, which could stick to the lens or get stuck between the lens and your
eye. As a result, your eyes can easily get infected due to these bacteria. I think you should buy a new pair.