protected void Button2_Click(object sender, EventArgs e)
    {
        string srchDescription = searchDescription.Text;
        string slctItem = DropDownList1.SelectedItem.ToString();

        con.Open();

        SqlCommand cmdForDescription = new SqlCommand("SELECT Описание FROM car_table WHERE Вносител = '" + slctItem + "'", con);
        string descriptionText = cmdForDescription.ExecuteScalar().ToString();
        bool containsDescription = descriptionText.Contains(srchDescription);

        if (containsDescription)
        {

            SqlCommand cmd = new SqlCommand("SELECT * FROM car_table WHERE Вносител = '" + slctItem + "'", con);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            GridView2.DataSource = ds;
            GridView2.DataBind();
            con.Close();
            Label2.Visible = true;

        }
    }