if not vs short of

if not

adv
  • Used to link a semantically weaker word to a semantically stronger word following the adverb, both sharing the same basic meaning, indicating the increased likelihood of the former. 

short of

phrase
  • Less than. 

  • Except; but; without resorting to; up to the point of. 

  • Insufficiently equipped with. 

How often have the words if not and short of occurred in a corpus of books? (source: Google Ngram Viewer )