enquiring vs inquiry

enquiring

noun
  • An instance of making an enquiry; an asking. 

adj
  • Curious, inquisitive or investigative. 

inquiry

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

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

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