Use simpler grouping instead of nested/sub queries.

Something of an oversight on my part, for missing this ability.

IslandoraSolrResults.inc

@@ -481,7 +481,7 @@ EOT;
 
   function _add_field(&$form, &$i, &$unprocessed_contents, &$types) {
     $type = NULL;
-    $temp = preg_split('/:/', trim($unprocessed_contents, '()'), 2);
+    $temp = preg_split('/:/', $unprocessed_contents, 2);
 
     if (!isset($type)) {
       if (trim($temp[0]) === '_query_') {
@@ -495,7 +495,7 @@ EOT;
       }
       else {
         $type = $temp[0];
-        $terms = trim($temp[1]);
+        $terms = trim($temp[1], '()');
       } 
     }
 

islandora_solr_search.module

@@ -385,7 +385,13 @@ function islandora_solr_search_block_form_submit($form, &$form_state) {
   }
 
   for ($iteration = 0; $iteration < count($fedora_terms); $iteration++) {
-    $searchString .= "_query_:\"{!dismax qf=" . $types[$iteration] . "}" . addcslashes($fedora_terms[$iteration], "\"'") . "\" " . $booleans[$iteration] . " ";
+    //FIXME (minor): t() should be changed to format_string() in this instance, in Drupal 7
+    //  The string isn't really translatable, just templated.
+    $searchString .= t("!field:(!query) !bool ", array(
+        '!field' => $types[$iteration], 
+        '!query' => $fedora_terms[$iteration],
+        '!bool' => $booleans[$iteration]
+    ));
   }
   $searchString = trim($searchString);
   $searchString = drupal_urlencode($searchString);