Unrecognized token AND

I am having problems in the next query:

This is my array of data

 String[] columns = new String[]
{ KEY_ROWELEMENTID, KEY_STUDYID,  KEY_ELEMENTCODE, KEY_ELEMENTNAME};

I create a cursor to this array where: The column KEY_ELEMENTCODE is equal to a varable result AND KEY_STUDYID is equal to a varable result AND

 Cursor c = 
ourDatabase.query(DATABASE_TABLEELEMENTS, columns,  KEY_ELEMENTCODE + "=" + elementRequest 
 + "AND" + KEY_STUDYID + 
"=" + idStudy, null, null, null, null);

What is the problem? I have debug and all variables has the correct values

Thanks