door prize vs luck of the draw

door prize

noun
  • A gift given to people who attend a meeting, party, event, etc., especially one which is given on a random basis to one or some of the attendees. 

  • A notional prize awarded to a cyclist who collides with the open door of a parked car. 

luck of the draw

noun
  • The random production of favorable or unfavorable results; chance. 

How often have the words door prize and luck of the draw occurred in a corpus of books? (source: Google Ngram Viewer )