code: func (model *Model) TrainQuery(term string) {
  	model.Lock()
  	if t, ok := model.Data[term]; ok {
  		t.Query++
  	} else {
  		model.Data[term] = &Counts{0, 1}
  	}
  	model.SuffDivergence++
  	update := model.SuffDivergence > model.SuffDivergenceThreshold
  	model.Unlock()
  	if update {
  		model.updateSuffixArr()
  	}
  }
docs: // Train using a search query term. This builds a second popularity
  // index of terms used to search, as opposed to generally occurring
  // in corpus text