low-level vs unserviceable

low-level

adj
  • relatively unimportant 

  • of, or relating to a program, or to code in which each statement corresponds to a single machine instruction 

  • detailed 

  • Situated or occurring at a lower level. 

  • not intense 

unserviceable

adj
  • Impractical. 

  • Not working (machinery, etc). 

  • Unusable; of no use. 

How often have the words low-level and unserviceable occurred in a corpus of books? (source: Google Ngram Viewer )