AsyncTask in DBHelper select?

Im trying to make my android app be more efficient, more fast so I wanted to make the select in dbhelper using asynctask but i cant manage to do it. This is the portion of code i want to make asynchronous. Thanks in advance and sorry for my bad english, im from Portugal

    public List<POI> todosPOIs() {
        List<POI> POIs = new ArrayList<POI>();

        SQLiteDatabase db = getWritableDatabase();
        Cursor cursor = db.rawQuery("SELECT * FROM " + NOME_TABELA, null);

        if (cursor.moveToFirst()) {
            do {
                POIs.add(new POI(Integer.parseInt(cursor.getString(0)), cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4),cursor.getString(5),cursor.getString(6),cursor.getString(7),cursor.getString(8),cursor.getString(9),cursor.getString(10),cursor.getString(11)));
            }
            while (cursor.moveToNext());
        }
        cursor.close();
        db.close();
        return POIs;//retorna o vetor POIs que inclui o resultado do select a todos os POIs
    }