private void sảnPhẩmToolStripMenuItem_Click(object sender, EventArgs e)
 {
     frm_SanPham sp = new frm_SanPham();
     sp.ShowDialog();
 }
        private void sảnPhẩmToolStripMenuItem_Click(object sender, EventArgs e)
        {
            frm_SanPham sp = new frm_SanPham();

            sp.ShowDialog();
        }