disagreement vs infighting

disagreement

noun
  • An argument or debate. 

  • A condition of not agreeing or concurring. 

infighting

noun
  • Fighting or quarreling among the members of a single group or side. 

  • Fighting with one's opponent closer than arm's length. 

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