condense vs flesh out

condense

verb
  • To be transformed from a gaseous state into a liquid state. 

  • To transform from a gaseous state into a liquid state via condensation. 

  • To concentrate toward the essence by making more close, compact, or dense, thereby decreasing size or volume. 

flesh out

verb
  • To complete; to create details from a basic outline, structure, or skeleton. 

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