root about vs trawl

root about

verb
  • To search for something in a similar manner. 

  • To rummage; to look for something in a somewhat aimless fashion. 

  • To forage by poking the snout here and there. 

trawl

verb
  • To make an exhaustive search for something within a defined area. 

  • To take (fish or other marine animals) with a trawl. 

  • To fish from a slow-moving boat. 

noun
  • A long fishing line having many short lines bearing hooks attached to it; a setline. 

  • A net or dragnet used for trawling. 

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