flash in the pan vs lengthy

flash in the pan

noun
  • A career notable for early success not followed by significant accomplishment. 

  • A transient occurrence with no long-term effect. 

lengthy

adj
  • Speaking or writing at length; long-winded. 

  • Having length; long and overextended, especially in time rather than dimension. 

  • a lengthy text 

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