psycho vs tough case

psycho

noun
  • A person who acts in a bizarre or dangerous manner. 

  • A class, at a college or university, in which psychology is taught. 

  • A person who is psychotic or otherwise insane. 

adj
  • Psychotic or otherwise insane. 

tough case

noun
  • A person who is difficult to work with. 

How often have the words psycho and tough case occurred in a corpus of books? (source: Google Ngram Viewer )