@RequestMapping(value = "/sach/add", method = RequestMethod.POST)
  public String create(SachUI sachUI, Model model) {
    TheLoaiSach theLoaiSach = theLoaiSachService.timTheLoaiSachByTen(sachUI.getTheLoaiUI());
    if (theLoaiSach != null) {
      Sach sach = SachMapper.convertToSach(sachUI, theLoaiSach);
      sachService.saveOrUpdate(sach);
    }

    return "redirect:/sach/list";
  }