docs: function (cb) {
  
                  if (!session.list.formData.search || !session.list.formData.search.length || !req.linz.model.list.search || !Array.isArray(req.linz.model.list.search)) {
                      return cb(null);
                  }
  
                  // Default the `$and` key.
                  if (!filters.$and) {
                      filters.$and = [];
                  }
  
                  async.map(req.linz.model.list.search, (field, fieldCallback) => {
  
                      linz.api.model.titleField(req.params.model, field, (err, titleField) => {
  
                          if (err) {
                              return fieldCallback(err);
                          }
  
                          fieldCallback(null, linz.api.query.fieldRegexp(titleField, session.list.formData.search));
  
                      });
  
                  }, (err, $or) => {
  
                      filters.$and.push({ $or });
  
                      return cb(null);
  
                  });
  
              }