litter box vs potpourri

litter box

noun
  • A box used to provide a soiling area for (usually) pet cats, generally filled with kitty litter, sand, clay chips, etc. 

potpourri

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

  • A ragout or stew of meat and vegetables. 

  • An anthology of miscellaneous prose. 

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

  • A medley of songs or music. 

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