private void btnTimKiem_Click(object sender, EventArgs e)
        {
            string strSQL = "";


            if (radTenDoiTac.Checked)
            {
                strSQL = "SELECT * FROM  [dbo].[T_NHANVIEN] WHERE [TenNhanVien] LIKE N'%" + StringTools.TrimSpace(txtThongTinTimKiem.Text) + "%'";
            }
            else if (radSoHieuXe.Checked)
            {
                strSQL = "SELECT * FROM  [dbo].[T_NHANVIEN] WHERE [FK_SoHieuXeLai] LIKE N'%" + StringTools.TrimSpace(txtThongTinTimKiem.Text) + "%'";
            }
            else if (radTheLaiXe.Checked)
            {
                strSQL = "SELECT * FROM  [dbo].[T_NHANVIEN] WHERE [SoTheLaiXe] LIKE N'%" + StringTools.TrimSpace(txtThongTinTimKiem.Text) + "%'";
            }
            else if (radSoDienThoai.Checked)
            {
                strSQL = "SELECT * FROM  [dbo].[T_NHANVIEN] WHERE [DiDong] LIKE N'%" + StringTools.TrimSpace(txtThongTinTimKiem.Text) + "%'";
            }

            mListOfNhanVien = NhanVien.GetNhanViens(strSQL);

            this.DialogResult = DialogResult.OK;
            this.Close();
        }