ahh, i see, make sure the form action passes the URL variable when it is submitted.
change:
<form class="DetailsPage Cool_Default" id="Results_Cool_Default" name="Results_Cool_Default" method="post" action="<?php echo (htmlentities($_SERVER["PHP_SELF"], ENT_QUOTES)); ?>">
to:
<form class="DetailsPage Cool_Default" id="Results_Cool_Default" name="Results_Cool_Default" method="post" action="<?php echo (htmlentities($_SERVER["PHP_SELF"], ENT_QUOTES)); ?><?php echo (isset($_SERVER["QUERY_STRING"]) && $_SERVER["QUERY_STRING"] != ""?"?".htmlentities($_SERVER["QUERY_STRING"], ENT_QUOTES):""); ?>">