leak out vs transpire

leak out

verb
  • To be revealed (especially, of information intended to be kept secret). 

  • To spill or pour out, because of a leak. 

transpire

verb
  • To become known; to escape from secrecy. 

  • Of plants, to give off water and waste products through the stomata. 

  • To happen, take place. 

  • To give off (vapour, waste matter etc.); to exhale (an odour etc.). 

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