feather one's nest vs look out for number one

feather one's nest

verb
  • To achieve benefits, especially financial ones, by taking advantage of the opportunities with which one is presented; to amass a comfortable amount of personal wealth. 

look out for number one

verb
  • To act in one's own interests; to act in a manner advantageous primarily to oneself. 

How often have the words feather one's nest and look out for number one occurred in a corpus of books? (source: Google Ngram Viewer )