investigate vs muckrake

investigate

verb
  • To inquire into or study in order to ascertain facts or information. 

  • To examine, look into, or scrutinize in order to discover something hidden or secret. 

  • To conduct an inquiry or examination. 

muckrake

verb
  • To search for and expose corruption or scandal, especially as a form of investigative journalism. 

noun
  • A rake for scraping up dung. 

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