manna vs windfall

manna

noun
  • The sugary sap of the manna gum tree which oozes out from holes drilled by insects and falls to the ground around the tree.http://www.museum.vic.gov.au/forest/plants/gum.html 

  • Any boon which comes into one's hands by good luck. 

  • Food miraculously produced for the Israelites in the desert in the book of Exodus. 

windfall

noun
  • A fruit that has fallen from a tree naturally, as from wind. 

  • Something that has been blown down by the wind. 

  • A sudden large benefit; especially, a sudden or unexpected large amount of money, as from lottery or sweepstakes winnings or an unexpected inheritance or gift. 

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