public DialogResult display_search(string i_str_key_search,string i_str_ma_truong, US_V_GD_CAU_HOI_YEU_CAU i_us)
 {
     load_data_2_cbo_truong();
     m_cbo_truong.SelectedValue = i_str_ma_truong;
     m_txt_key_search.Text = i_str_key_search;
     m_us_cau_hoi_yeu_cau = i_us;
     m_e_form_load = e_form_load.SEARCH_ON_LOAD_YES;
     m_e_co_lich_su_yn = e_tim_so_trong_lich_su_goi.CO_HOAC_KO_TRONG_LICH_SU_GOI;
     this.ShowDialog();
     return m_dlg_result;
 }
 public DialogResult display(US_V_GD_CAU_HOI_YEU_CAU i_us)
 {
     load_data_2_cbo_truong();
     m_us_cau_hoi_yeu_cau = i_us;
     m_e_form_load = e_form_load.SEARCH_ON_LOAD_NO;
     this.ShowDialog();
     return m_dlg_result;
 }