def _query(self):  # pylint: disable=E0202
        """
        Query WMI using WMI Query Language (WQL) & parse the results.

        Returns: List of WMI objects or `TimeoutException`.
        """
        formated_property_names = ",".join(self.property_names)
        wql = "Select {property_names} from {class_name}{filters}".format(
            property_names=formated_property_names, class_name=self.class_name, filters=self.formatted_filters
        )
        self.logger.debug(u"Querying WMI: {0}".format(wql))

        try:
            # From: https://msdn.microsoft.com/en-us/library/aa393866(v=vs.85).aspx
            flag_return_immediately = 0x10  # Default flag.
            flag_forward_only = 0x20
            flag_use_amended_qualifiers = 0x20000

            query_flags = flag_return_immediately | flag_forward_only

            # For the first query, cache the qualifiers to determine each
            # propertie's "CounterType"
            includes_qualifiers = self.is_raw_perf_class and self._property_counter_types is None
            if includes_qualifiers:
                self._property_counter_types = CaseInsensitiveDict()
                query_flags |= flag_use_amended_qualifiers

            raw_results = self.get_connection().ExecQuery(wql, "WQL", query_flags)

            results = self._parse_results(raw_results, includes_qualifiers=includes_qualifiers)

        except pywintypes.com_error:
            self.logger.warning(u"Failed to execute WMI query (%s)", wql, exc_info=True)
            results = []

        return results
Query WMI using WMI Query Language (WQL) & parse the results.

        Returns: List of WMI objects or `TimeoutException`.