leave alone vs supersede

leave alone

verb
  • To desist or refrain from involvement with. 

  • To stop bothering (a person). 

supersede

verb
  • To displace in favour of itself. 

  • To take the place of. 

noun
  • An updated newsgroup post that supersedes an earlier version. 

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