Complex sentence: After a person has done hundreds of readings their skills may improve to the point where they may start believing they can read minds, asking themselves if their success is because of psychology, intuition or a psychic ability.
Split into simpler sentences: After a person has performed hundreds of readings, their skills may improve to the point where they may start believing they can read minds. They may ask themselves if their success is because of psychology, intuition or a psychic ability.