private void thânNhânToolStripMenuItem_Click(object sender, EventArgs e)
        {
            frmChuyenMon f = new frmChuyenMon();

            f.ShowDialog();
        }
 private void thânNhânToolStripMenuItem_Click(object sender, EventArgs e)
 {
     frmChuyenMon f = new frmChuyenMon();
     f.ShowDialog();
 }