fixed error in id_search

site/public/id_search.php

@@ -73,7 +73,7 @@ include '../ops_api.php'
     <br><br>
 
     <?php
-    if ($result['title']):
+    if (isset($result['title'])):
     ?>
 
     Title:
@@ -105,7 +105,7 @@ include '../ops_api.php'
     ?>
 
     <?php
-    if ($result['abstract']):
+    if (isset($result['abstract'])):
     ?>
 
     Abstract: