Hi!
If I undestand correctly you have it on a results page, and use the live results loader feature. The resuls counter/nothing found has no effect on that, as this is a theme related feature in this case. Those elements only affect the live results, when the plugin displays them in it’s own live results container.
If you are editing the theme, you can add these messages there, within the #search-results element. I believe the results count can be obtained like so:
global $wp_query;
echo $wp_query->found_posts.' results found.';
..and to check if there are any results, you can wrap the results list within
<?php if ( have_posts() ) : ?>
// Print results list here
<?php else : ?>
// No resulst here
<?php endif; ?>
I hope this helps!