code: protected function transformDSLTermToString($dslTerm) {
          $string = "";
          if (is_array($dslTerm)) {
              $key = key($dslTerm);
              $value = $dslTerm[$key];
              if (is_string($key))
                  $string .= "$key:";
          }
          else
              $value = $dslTerm;
          /**
           * If a specific key is used as key in the array
           * this should translate to searching in a specific field (field:term)
           */
          if (strpos($value, " ") !== false)
              $string .= '"' . $value . '"';
          else
              $string .= $value;
          return $string;
      }
docs: A naive transformation of possible term and wildcard arrays in a DSL
  query
  
  @return string
  @param mixed $dslTerm