bombproof vs sanctuary

bombproof

noun
  • An air-raid shelter, a structure designed to give protection against air raids and bombs. 

verb
  • To make resistant to bomb blasts. 

adj
  • Sufficiently strong to resist the effects of a blast from a bomb. 

sanctuary

noun
  • A place of safety, refuge, or protection. 

  • A state of being protected, asylum. 

  • The consecrated (or sacred) area of a church or temple around its tabernacle or altar. 

  • My car is a sanctuary, where none can disturb me except for people who cut me off. 

  • An area set aside for protection. 

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