Complex sentence: Some may have erroneous beliefs that the crease has grown because they moved their hands in a different way to other people, and they may be ashamed of it and try to hide it while others may think that the rest of the world has similar hand lines.
Split into simpler sentences: Some may have erroneous beliefs that the crease has grown because they moved their hands in a way different from other people, resulting in shame and an attempt to hide it. Others may simply think that the rest of the world has similar hand lines.