Search Record with Multiple TextBox in Multiple Columns in ASP.Net

code is fine there is no error ,.,. 

this code is working with all text boxes..

 protected void Button2_Click(object sender, EventArgs e)
    {
        if (TextBox2.Text == "" && TextBox3.Text == "" && TextBox4.Text == "")
        {
            DateTime dt = Convert.ToDateTime(TextBox1.Text);
            SqlCommand cmd = new SqlCommand("SELECT * FROM Transactions where report_type = @report_type and  dateadd(dd, datediff(dd,0, [R_date]), 0) = @R_date  ");

            cmd.Connection = con;
            cmd.Parameters.Add("@report_type", SqlDbType.NVarChar).Value = DropDownList1.SelectedValue;
            cmd.Parameters.Add("@R_date", SqlDbType.DateTime).Value = dt.Date;
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();
        }
        else if (TextBox2.Text != "")
        {
            con.Open();
            string s = ("Select * from Transactions where idcount like '%" + TextBox2.Text + "%' or Patient_ID_NO like '%" + TextBox2.Text + "%'or Patient_no like '%" + TextBox2.Text + "%'");
            SqlCommand cmd = new SqlCommand(s, con);
            cmd.Parameters.Add("@idcount", SqlDbType.Decimal).Value = TextBox2.Text;
            cmd.Parameters.Add("@Patient_ID_NO", SqlDbType.Decimal).Value = TextBox2.Text;
            cmd.Parameters.Add("@Patient_no", SqlDbType.Int).Value = TextBox2.Text;

            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();
            TextBox2.Text = "";

        }
        else if (TextBox3.Text != "")
        {
            SqlCommand cmd = new SqlCommand("SELECT * FROM Transactions where Patient = @Patient   ");
            cmd.Connection = con;
            cmd.Parameters.Add("@Patient", SqlDbType.NVarChar).Value = TextBox3.Text;
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();
            TextBox3.Text = "";

        }
        else
        {
            DateTime dt = Convert.ToDateTime(TextBox4.Text);
            SqlCommand cmd = new SqlCommand("SELECT * FROM Transactions where dateadd(dd, datediff(dd,0, [R_date]), 0) = @R_date  ");
            cmd.Connection = con;
            //cmd.Parameters.Add("@report_type", SqlDbType.NVarChar).Value = DropDownList1.SelectedValue;
            cmd.Parameters.Add("@R_date", SqlDbType.DateTime).Value = dt.Date;
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();
            TextBox4.Text = "";
        }
        Button3.Enabled = true;
    }