mixed bag vs multeity

mixed bag

noun
  • A group of entities with few characteristics in common. 

  • Any bag containing a mixture of something. 

  • Something tending to have both good and bad results or characteristics; something having a mixture of advantages and disadvantages. 

multeity

noun
  • manifoldness; multiplicity; the quality of being many. 

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