private void button1_Click(object sender, EventArgs e)
{
QuanLyController quanLy = new QuanLyController();
XemAllThongKe allThongKe = new XemAllThongKe(quanLy.AllThongKe(dateTimePicker1.Value));
allThongKe.ChiTietTieuDung();
allThongKe.Show();
}