如何加上搜索功能，并且和原来的排序结合

我现在只是写好了搜索功能，在代码的最下面我加了一个搜索btnserch_Click。但是不能很好的和排序结合在一起。需求在那个图片上写了 
下面是排序的程序： protected void Page_Load(object sender, EventArgs e)
    {
        if (string.IsNullOrEmpty(Request.QueryString["sn"]) && string.IsNullOrEmpty(Request.QueryString["game"]))
        {
            BindGrid_null();
        }        if (!string.IsNullOrEmpty(Request.QueryString["sn"]))
        {
            BindGrid_sn(Request.QueryString["sn"]);
        }        if (!string.IsNullOrEmpty(Request.QueryString["game"]))
        {
            BindGrid_game(Request.QueryString["game"]);
        }        if (tserch.Text.Trim() != "")
        {
        }
    }    private void BindGrid_null()
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conn"].ConnectionString);        string cmd1 = "select game,sn from [order]";
        SqlDataAdapter sda1 = new SqlDataAdapter(cmd1, con);
        DataSet ds1 = new DataSet();
        con.Open();
        sda1.Fill(ds1, "order");
        DataTable dt = ds1.Tables["order"];
        con.Close();        foreach (DataRow row in dt.Rows)
        {
            Response.Write("<table width=250 height=20 border=0 cellspacing=0 cellpadding=0><tr><td width=100><a href=index.aspx?game=" + row["game"] + ">" + (row["game"]) + "</a></td><td width=150><a href=index.aspx?sn=" + row["sn"] + ">" + (row["sn"]) + "</a></td></tr></table>");
        }
    }
    private void BindGrid_game(string game)
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conn"].ConnectionString);        string cmd = string.Empty;        if (string.IsNullOrEmpty(game))
            cmd = "select game,sn from [order]";
        else
            cmd = "select game,sn from [order] where game= '" + game + "'union all select game,sn from [order] where game <> '" + game + "' ";
        SqlDataAdapter sda = new SqlDataAdapter(cmd, con);
        DataSet ds = new DataSet();
        con.Open();
        sda.Fill(ds, "order");
        DataTable dt = ds.Tables["order"];
        con.Close();        foreach (DataRow row in dt.Rows)
        {
            Response.Write("<table width=250 height=20 border=0 cellspacing=0 cellpadding=0><tr><td width=100><a href=index.aspx?game=" + row["game"] + ">" + (row["game"]) + "</a></td><td width=150><a href=index.aspx?sn=" + row["sn"] + ">" + (row["sn"]) + "</a></td></tr></table>");
        }
    }    private void BindGrid_sn(string sn)
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conn"].ConnectionString);        string cmd = string.Empty;        if (string.IsNullOrEmpty(sn))
            cmd = "select game,sn from [order]";
        else
            cmd = "select game,sn from [order] where sn= '" + sn + "'union all select game,sn from [order] where sn <> '" + sn + "' ";
        SqlDataAdapter sda = new SqlDataAdapter(cmd, con);
        DataSet ds = new DataSet();
        con.Open();
        sda.Fill(ds, "order");
        DataTable dt = ds.Tables["order"];
        con.Close();        foreach (DataRow row in dt.Rows)
        {
            Response.Write("<table width=250 height=20 border=0 cellspacing=0 cellpadding=0><tr><td width=100><a href=index.aspx?game=" + row["game"] + ">" + (row["game"]) + "</a></td><td width=150><a href=index.aspx?sn=" + row["sn"] + ">" + (row["sn"]) + "</a></td></tr></table>");
        }
    }
    protected void btnserch_Click(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conn"].ConnectionString);
        string box = tserch.Text.ToString();        string cmd = "select game,sn from [order] where  game='" + box + "' ";
        SqlDataAdapter sda = new SqlDataAdapter(cmd, con);
        DataSet ds = new DataSet();        con.Open();
        sda.Fill(ds, "order");
        DataTable dt = ds.Tables["order"];
        con.Close();        foreach (DataRow row in dt.Rows)
        {
            Response.Write("<table width=250 height=20 border=0 cellspacing=0 cellpadding=0><tr><td width=100><a href=index.aspx?game=" + row["game"] + ">" + (row["game"]) + "</a></td><td width=150><a href=index.aspx?sn=" + row["sn"] + ">" + (row["sn"]) + "</a></td></tr></table>");
        }
    }