Try this:
open this PHP file:
/templates/YOUR_TEMPLATE/html/mod_virtuemart_search/default.php
find these lines:
$plugin=JPluginHelper::getPlugin('system','flexibleTemplate');
$params=new JParameter($plugin->params);
$app = JFactory::getApplication('site');
$template = $app->getTemplate();
$FlexiblePATH = 'templates/'.$template.'/html/com_virtuemart/assets/Flexible/';
//JHTML::script("jquery.carouFredSel-6.2.1-packed.js", $FlexiblePATH);
include_once dirname(__FILE__) . '/../com_virtuemart/assets/includes/flexibleMartGlobal.php';
and remove them all and see if things start working.
If everything starts working just fine, then remove those one lines (comment out with // at the beginning) one-by-one and try to figure out what specific line causes the problem.
Furthermore, you can enable the "error reporting" to MAX and see the error report and figure out what line is generating problem.
Regards,
Support