No, there aren't spiritual principles that enable us to get what we want from God.
The Bible says this about faith:

(Hebrews 11:6 NIV) And without faith it is impossible to please God, because anyone who comes to him must believe that he exists and that he rewards those who earnestly seek him.

Everything is subject to the will of God. Yes, Jesus said if have enough faith you can cause this mountain to be moved to the sea. But you can't do anything that's outside the will of God.

I prayed for the health of my unborn son. He was stillborn.
I prayed for the health of my unborn daughter. She was stillborn.
I prayed for the health of my wife. She still lost her transplanted kidney. She still died at the age of 30.