private void chiTiếtNhậpToolStripMenuItem_Click(object sender, EventArgs e)
 {
     frm_CTNhap ctn = new frm_CTNhap();
     ctn.ShowDialog();
 }
        private void chiTiếtNhậpToolStripMenuItem_Click(object sender, EventArgs e)
        {
            frm_CTNhap ctn = new frm_CTNhap();

            ctn.ShowDialog();
        }