conjure up vs dream up

conjure up

verb
  • To generate (an image or an idea) in one's mind. 

  • To create or produce something, seemingly magically. 

  • To call up or command a spirit or devil by an incantation. 

dream up

verb
  • To have an imaginative, unusual or foolish idea, to invent something unreal. 

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