diff --git a/common/db.js b/common/db.js
index 5861346afabfc35895b7b41b0c8ff33b4b5fbd8e..5b0a2d6f990b1d3afeb1456ab03b5556efdb8c12 100644
--- a/common/db.js
+++ b/common/db.js
@@ -1,5 +1,5 @@
-const logger = require('./common/logger.js');
-var sqlite3  = require('sqlite3').verbose();
+const logger = require.main.require('./common/logger.js');
+var sqlite3  = require.main.require('sqlite3').verbose();
 
 /* The kara table is defined as follows:
  *
@@ -27,23 +27,21 @@ var sqlite3  = require('sqlite3').verbose();
 
 class KaraDatabase {
 
-    /* Private members
-     * - #m_karaPath: String
-     * - #m_db: sqlite3 database */
-    #m_karaPath;
-    #m_db;
-
     /* The constructor
-     * - karaPath: String */
+     * - karaPath: String
+     *
+     * Private members
+     * - m_karaPath: String
+     * - m_db: sqlite3 database */
     constructor(karaPath) {
-        this.#m_karaPath = karaPath;
-        this.#m_db       = new sqlite3.Database(this.m_karaPath);
+        this.m_karaPath = karaPath;
+        this.m_db       = new sqlite3.Database(this.m_karaPath);
         logger.log("info", "Create database from file " + karaPath);
     }
 
     /* Call this as a destructor */
     close() {
-        this.#m_db.close();
+        this.m_db.close();
         logger.log("info", "Close database " + karaPath);
     }
 
@@ -55,7 +53,7 @@ class KaraDatabase {
              FROM kara
              WHERE string LIKE ? OR author COLLATE nocase = ?`
         ;
-        db.all(sql, [queryString, queryString], (err, rows) => {
+        db.all(sql, [`%${queryString}%`, queryString], (err, rows) => {
             if (err) {
                 throw err;
             }
@@ -65,3 +63,5 @@ class KaraDatabase {
         });
     }
 }
+
+module.exports = KaraDatabase;
diff --git a/test/common b/test/common
new file mode 120000
index 0000000000000000000000000000000000000000..83323993bad347881e1630f2c12d3e3f25106c0d
--- /dev/null
+++ b/test/common
@@ -0,0 +1 @@
+../common/
\ No newline at end of file
diff --git a/test/node_modules b/test/node_modules
new file mode 120000
index 0000000000000000000000000000000000000000..ea095f3ded1684255254ba6a838b689eb632efbe
--- /dev/null
+++ b/test/node_modules
@@ -0,0 +1 @@
+../node_modules/
\ No newline at end of file
diff --git a/test/test_db.js b/test/test_db.js
new file mode 100644
index 0000000000000000000000000000000000000000..186b187764950b298009c4ba9e2e2e006cc23e66
--- /dev/null
+++ b/test/test_db.js
@@ -0,0 +1,4 @@
+const logger       = require.main.require('../common/logger.js');
+const KaraDatabase = require.main.require('../common/db.js');
+
+var myDb = new KaraDatabase("/home/kara/kara.db");