collage vs potpourri

collage

noun
  • The technique of producing a work of art of this kind. 

  • A picture made by sticking other pictures onto a surface. 

  • A composite object or collection (abstract or concrete) created by the assemblage of various media; especially for a work of art such as text, film, etc. 

verb
  • To make into a collage. 

potpourri

noun
  • An anthology of miscellaneous prose. 

  • A ragout or stew of meat and vegetables. 

  • A mixture of dried fragrant plant material, often in a decorative bowl, used to scent a room. 

  • A collection of various things; an assortment, mixed bag or motley. 

  • A medley of songs or music. 

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