exploration vs inquiry

exploration

noun
  • The process of exploring. 

  • A physical examination of a patient. 

  • The (pre-)mining process of finding and determining commercially viable ore deposits (after prospecting), also called mineral exploration. 

  • The process of penetrating, or ranging over for purposes of (especially geographical) discovery. 

inquiry

noun
  • Search for truth, information, or knowledge; examination of facts or principles; research; investigation 

  • The act of inquiring; a seeking of information by asking questions; interrogation; a question or questioning. 

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