--- handlers.inc
+++ (clipboard)
@@ -970,12 +970,12 @@
     return $handler;
   }
 
-  if (preg_match('/^(\w+[+ ])+\w+$/', $str)) {
+  if (preg_match('/^([\w-]+[+ ])+[\w-]+$/', $str)) {
     // The '+' character in a query string may be parsed as ' '.
     $handler->operator = 'or';
     $handler->value = preg_split('/[+ ]/', $str);
   }
-  else if (preg_match('/^(\w+,)*\w+$/', $str)) {
+  else if (preg_match('/^([\w-]+,)*[\w-]+$/', $str)) {
     $handler->operator = 'and';
     $handler->value = explode(',', $str);
   }