Index: modules/custom_search_taxonomy/custom_search_taxonomy.admin.inc
===================================================================
--- modules/custom_search_taxonomy/custom_search_taxonomy.admin.inc	(revision 52)
+++ modules/custom_search_taxonomy/custom_search_taxonomy.admin.inc	(working copy)
@@ -42,6 +42,12 @@
         '#description'    => t('Choose which selector type to use.'),
         '#default_value'  => variable_get('custom_search_voc' . $voc->vid . '_selector', 'disabled'),
       );
+      $form[$voc->name]['custom_search_voc' . $voc->vid . '_selector_depth'] = array(
+        '#type'           => 'textfield',
+        '#title'          => t('Depth'),
+        '#default_value'  => variable_get('custom_search_voc' . $voc->vid . '_selector_depth', 0),
+        '#description'    => t('Define the maximum depth of terms being displayed. The default value is "0" which disables the limit.'),
+      );
       $form[$voc->name]['custom_search_voc' . $voc->vid . '_selector_label_visibility'] = array(
         '#type'           => 'checkbox',
         '#title'          => t('Display label'),
Index: modules/custom_search_taxonomy/custom_search_taxonomy.install
===================================================================
--- modules/custom_search_taxonomy/custom_search_taxonomy.install	(revision 52)
+++ modules/custom_search_taxonomy/custom_search_taxonomy.install	(working copy)
@@ -20,6 +20,7 @@
   $vocabularies = taxonomy_get_vocabularies();
   foreach ($vocabularies as $voc) {
     variable_del('custom_search_voc' . $voc->vid . '_selector');
+    variable_del('custom_search_voc' . $voc->vid . '_selector_depth');
     variable_del('custom_search_voc' . $voc->vid . '_selector_label_visibility');
     variable_del('custom_search_voc' . $voc->vid . '_selector_label');
     variable_del('custom_search_voc' . $voc->vid . '_selector_all');
Index: modules/custom_search_taxonomy/custom_search_taxonomy.module
===================================================================
--- modules/custom_search_taxonomy/custom_search_taxonomy.module	(revision 52)
+++ modules/custom_search_taxonomy/custom_search_taxonomy.module	(working copy)
@@ -62,7 +62,8 @@
           if (variable_get('custom_search_' . $delta . 'voc' . $voc->vid . '_selector', 'disabled') != 'disabled') {
             $options = array();
             $options['c-all'] = variable_get('custom_search_' . $delta . 'voc' . $voc->vid . '_selector_all', CUSTOM_SEARCH_ALL_TEXT_DEFAULT);
-            $terms = taxonomy_get_tree($voc->vid);
+            $vocabulary_depth = (!variable_get('custom_search_' . $delta . 'voc' . $voc->vid . '_selector_depth', 0)) ? NULL : variable_get('custom_search_' . $delta . 'voc' . $voc->vid . '_selector_depth', 0);
+            $terms = taxonomy_get_tree($voc->vid, 0, -1, $vocabulary_depth);
             foreach ($terms as $term) {
               $options['c-' . $term->tid] = (drupal_substr(variable_get('custom_search_' . $delta . 'voc' . $voc->vid . '_selector', 'disabled'), 0, 6) == 'select') ? str_repeat('- ', $term->depth) . $term->name : $term->name ;
             }