Deep async for parsing RxTerm data

app.js

app.get('...', function(req, res){
  
  var lines = [...];
  var lineFns = lines.map(function(line){
    return function(cbLines){
      var words = line.split(' ');
      var wordFns = words.map(function(word){
        return function(cbWords){
          Model.find({term: word}, function(err, docs){
            if(docs.length === 0)
              // null for error and null for value because nothing found
              cbWords(null, null);
            else{
              // do the proper search to find any match data you want
              cbWords(null, matchData);
            }
          });
        };
      });
      // word functions are created so pass them to the async call
      async.parallel(wordFns, cbLines);
    };
  });
  // all line functions have been defined now... whew...
  async.parallel(lineFns, function(err, results){
    // here, err will be any errors encountered during the CB process
    //    and results will be an array of arrays of data containing matches or null
    res.send(results);
    // for example, if you want to just see everything in the page as it is.
  });
});