diff --git a/lib/SearchEngine.js b/lib/SearchEngine.js
index <HASH>..<HASH> 100644
--- a/lib/SearchEngine.js
+++ b/lib/SearchEngine.js
@@ -5,6 +5,7 @@ module.exports = function (options) {
 
     var SearchIndex = require('search-index');
     var path = require('path');
+    var fs = require('extfs');
 
     var preparer = require('./Preparer.js');
     var cfi = require('./CFI.js');
@@ -18,8 +19,11 @@ module.exports = function (options) {
 
     this.indexing = function (pathToEpubs, callback) {
 
+        if(fs.isEmptySync(pathToEpubs)) 
+          return callback(new Error('Can`t index empty folder: ' + pathToEpubs));
+        
         console.log("normalize epub content");
-
+        
         path.normalize(pathToEpubs);
 
         preparer.normalize(pathToEpubs, function (dataSet) {
@@ -103,4 +107,8 @@ module.exports = function (options) {
     this.empty = function (callback) {
         si.empty(callback);
     };
+    
+    this.close = function(callback) {
+        si.close(callback);
+    }
 };
\ No newline at end of file
- added contract to check epub data folder is not empty
- added close()