manipulate vs pinch off

manipulate

verb
  • To move, arrange or operate something using the hands 

  • To influence or control someone in order to achieve a specific purpose, especially one that is unknown to the one being manipulated and beneficial to the manipulator; to use 

  • To handle and move a body part, either as an examination or for a therapeutic purpose 

  • To influence, manage, direct, control or tamper with something 

pinch off

verb
  • To separate (something) from something else, using a pinching motion. 

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