inquiry vs zoology

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. 

zoology

noun
  • A treatise on this science. 

  • The part of biology relating to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct. 

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