hard candy vs lollipop

hard candy

noun
  • A candy prepared from one or more syrups boiled to a temperature of 160°C (320°F), thereafter becoming stiff and brittle at room temperature. 

lollipop

noun
  • An item of confectionery consisting of a piece of candy/sweet attached to a stick. 

  • Something having the shape of a lollipop: a linear stem connected to a round body. 

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