sherbet vs thickshake

sherbet

noun
  • A food of frozen fruit juice with a dairy product such as milk added; a sorbet with dairy ingredients. 

  • An effervescent powder made of bicarbonate of soda, sugar and flavourings, intended to be eaten alone or mixed with water to make a drink. 

  • A traditional West and South Asian sweet drink prepared from fruits or flower petals. 

  • An alcoholic drink, especially beer. 

thickshake

noun
  • A beverage consisting of milk and ice cream mixed together, often with other flavorings as well. 

  • An imitation milkshake (in locales where "milkshake" refers to the drink specified above), often containing no milk. 

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