You are right, once blind, no amount of "effort" or "will" to see, will make it happen.
But Jesus can do the miracle.
Mr 10:51 And Jesus answered and said unto him, What wilt thou that I should do unto thee? The blind man said unto him, Lord, that I might receive my sight.
52 And Jesus said unto him, Go thy way; thy faith hath made thee whole. And immediately he received his sight, and followed Jesus in the way.
That's why Jesus said he came to earth.
Joh 9:39 ¶ And Jesus said, For judgment I am come into this world, that they which see not might see; and that they which see might be made blind.
