in contention vs thorny

in contention

prep
  • Used other than figuratively or idiomatically: see in, contention. 

  • Contending for a title or championship. 

thorny

adj
  • Having thorns or spines 

  • Troublesome or vexatious 

  • Aloof and irritable 

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