how to find records between two string dates SQLITE - Android

 String start = "9-4-2015";
 String end = "11-4-2015";
 SimpleDateFormat sdf = new SimpleDateFormat("d-M-yyyy");
 List<IncomeModel> allToDos = db.getAllIncomesWeeks();

 for (IncomeModel todo : allToDos) {
    DatabaseDate = todo.getDate();
    try {
          if (sdf.parse(start).before(sdf.parse(end))) {
               incomeModel.add(todo);
               sum = sum + Integer.parseInt(todo.getAmount());
              }
        } catch (NumberFormatException | ParseException e) {
           e.printStackTrace();
    }
  }
  tvSum.setText(sum + "");

I needs a records between start date and end dates. I also Tried This Query

"SELECT * FROM expenses WHERE date BETWEEN '"+ start + "' AND '" + end + "'"

But It's Also Shows Wrong Data.