enslavement vs exploitation

enslavement

noun
  • The act of enslaving or the state of being a slave; bondage 

exploitation

noun
  • The act or result of forcibly depriving someone of something to which they have a natural right. 

  • The improper use of something for selfish purposes. 

  • The act of utilizing something; industry. 

  • The marketing and promotion of a film. 

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