doorstep vs go out on the knocker

doorstep

noun
  • An outside step leading up to the door of a building, usually a home. 

  • One's immediate neighbourhood or locality. 

  • A thick slice, especially of bread. 

verb
  • To visit one household after another to solicit sales, charitable donations, political support, etc. 

  • To corner somebody for an unexpected interview. 

go out on the knocker

How often have the words doorstep and go out on the knocker occurred in a corpus of books? (source: Google Ngram Viewer )