indistinct vs structureless

indistinct

adj
  • not clearly defined or not having a sharp outline; faint or dim 

  • hazy or vague 

  • difficult to understand through being muffled or slurred 

structureless

adj
  • Lacking structure. 

  • Lacking structures, edifices. 

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