manipulation vs power struggle

manipulation

noun
  • The practice of manipulating or the state of being manipulated. 

  • The usage of psychological influence over a person, event, or situation to gain a desired outcome. 

  • The skillful use of the hands in, for example, chiropractic. 

power struggle

noun
  • A situation where two or more people or groups fight to gain dominance over each other. 

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