Searching crystal reports in C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb;
namespace SakshiHospital
{
    public partial class DebitRpt: Form
    {
        public DebitRpt()
        {
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(721, 439);
            this.Name = "Cry_Report";
            this.Text = "Cry_Report";
            this.Load += new System.EventHandler(this.DebitRpt_Load);
            this.ResumeLayout(false);
            this.SuspendLayout();
            InitializeComponent();
        }
        private void DebitRpt_Load(object sender, EventArgs e) {}
        private void btnSearch_Click(object sender, EventArgs e)
        {
            try
            {
                // string bill_no = "B_00" + txtbillno.Text;
                DataSet ds = new DataSet();
                // con = new OleDbConnection(ConfigurationManager.ConnectionStrings["connect"].ConnectionString);
                OleDbConnection con = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=ClientMgmtDb1.accdb;");
                con.Open();
                OleDbDataAdapter da = new OleDbDataAdapter();
                // if(txtbillno.Text.Trim().Length==0)
                if (txtdebitnote.Text != "")
                {
                    // MessageBox.Show("Enter Bill number");
                    da = new OleDbDataAdapter("select ID,NAME,Debit_Number,Date,Address,PO_Number,PO_Date,Narat,Quantity,Rate,Total_price,amount FROM Debit_Mst where Debit_Number='" + txtdebitnote.Text.Trim() + "'", con);
                }
                da.Fill(ds, "Debit");
                if (ds.Tables.Count > 0)
                {
                    Debitrptcr cr = new Debitrptcr();
                    // Bill2 cr = new Bill2();
                    cr.SetDataSource(ds.Tables[0]);
                    this.crystalReportViewer1.ReportSource = cr;
                    this.crystalReportViewer1.Show();
                    //// }
                }
                con.Close();
            } catch (OleDbException s)
            {
                MessageBox.Show("Server Problem...");
            }
        }
        private void txtdebitnote_TextChanged(object sender, EventArgs e) {
            txtdebitnote.BackColor = System.Drawing.Color.Aquamarine;
            this.AcceptButton = btnSearch;
        }
    }
}