Complex sentence: He has attracted criticisms from professionals in the medical field, who say his treatments rely on the placebo effect and that he sells "false hope" with claims that his techniques can cure AIDS or cancer or significantly extend someone's lifespan.
Split into simpler sentences: He has attracted criticisms from professionals in the medical field, who say his treatments rely on the placebo effect and that he sells "false hope". He claims to have techniques to cure AIDS or cancer or significantly extend someone's lifespan.