diff --git a/mobile.netbiblio.php b/mobile.netbiblio.php
index 64091ee..e12d2eb 100644
--- a/mobile.netbiblio.php
+++ b/mobile.netbiblio.php
@@ -190,19 +190,19 @@ class NetBiblio extends WebService
     public function GetWishes()
     {
         $books = $this->getUser()->getWishes();
-        return array_values(array_map(array($this, 'AddFiles'), $books));
+        return array_values($this->AddFiles($books));
     }
 
     public function GetCirculations()
     {
         $circulations = $this->getUser()->getCirculations();
-        return array_values(array_map(array($this, 'AddFiles'), $circulations));
+        return array_values($this->AddFiles($circulations));
     }
 
     public function GetOldCirculations()
     {
         $circulations = $this->getUser()->getOldCirculations();
-        return array_values(array_map(array($this, 'AddFiles'), $circulations));
+        return array_values($this->AddFiles($circulations));
     }
 
     public function AddWish($bookNr)
@@ -222,7 +222,7 @@ class NetBiblio extends WebService
         $codes = json_decode($codes, true);
         $codes = array_map('intval', $codes);
         $books = AudioBook::findBy('NoticeNr', $codes, true);
-        return array_values(array_map(array($this, 'AddFiles'), $books));
+        return array_values($this->AddFiles($books));
     }
 
     private function GetFiles(array $ids)
@@ -247,16 +247,24 @@ class NetBiblio extends WebService
         return json_decode($json, true);
     }
 
-    private function AddFiles(array $book)
+    private function AddFiles(array $books)
     {
-        $files = $this->GetFiles(array($book['code']));
+        if(isset($books['code'])) {
+            $result = $this->AddFiles(array($books));
+            return reset($result);
+        }
 
-        if (is_array($files) && isset($files[$book['code']])) {
-            $book['files'] = $files[$book['code']];
-        } else {
-            $book['files'] = array();
+        $ids = array_map(function($b) { return $b['code']; }, $books);
+        $files = $this->GetFiles($ids);
+        foreach($books as $k => $b) {
+            if(isset($files[$b['code']])) {
+                $books[$k]['files'] = $files[$b['code']];
+            } else {
+                // we need to have an empty array for mobile apps compatibility.
+                $books[$k]['files'] = array();
+            }
         }
-        return $book;
+        return $books;
     }
 
     public function FindBook($code)
@@ -283,7 +291,7 @@ class NetBiblio extends WebService
         $ids = Connection::execute($sql)->to_array();
         $ids = array_map(function($a) { return $a['NoticeId']; }, $ids);
         $books = AudioBook::findBy('NoticeId', $ids, true);
-        return array_values(array_map(array($this, 'AddFiles'), $books));
+        return array_values($this->AddFiles($books));
     }
 
     public function Search($query, $start, $limit)
@@ -376,8 +384,10 @@ class NetBiblio extends WebService
             'facets' => $results['facet_counts']['facet_fields'],
         );
 
-        foreach ($results['response']['docs'] as $doc) {
-            $data[] = $this->AddFiles((array) $doc);
+        if($results['response']['docs']) {
+            $books = array_map(function($o) { return (array) $o; }, $results['response']['docs']);
+            $books = $this->AddFiles($books);
+            $data = array_merge($data, $books);
         }
 
         return $data;
@@ -431,7 +441,7 @@ class NetBiblio extends WebService
 
         $ids = array_map(function($r) { return $r['id']; }, $results['response']['docs']);
         $books = AudioBook::findBy('NoticeID', $ids, true);
-        $books = array_map(array($this, 'AddFiles'), $books);
+        $books = $this->AddFiles($books);
 
         $data = array();
         foreach($books as $b) {