It is possible that your overrides are outdated.
You need to add the message.
Replace the last endif (which checks if there are items) with the following code.
<?php else: ?>
<?php if(!$this->params->get('googleSearch')): ?>
<!-- No results found -->
<div id="genericItemListNothingFound">
<p><?php echo JText::_('K2_NO_RESULTS_FOUND'); ?></p>
</div>
<?php endif; ?>
<?php endif; ?>
