coursebook vs handbook

coursebook

noun
  • A textbook, a book designed to accompany a specific academic course, or one specified by the writers of the course to be read by its students. 

handbook

noun
  • A topically organized book of reference on a certain field of knowledge, regardless of size. 

  • A place where illicit bets can be placed. 

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