Dynamic Where clause

Dynamic LINQ clause with  Join that allows items to  be concatenated.

 if (FormLoaded)
            {
                var loans = dc.TRACKING_FILEs;
                var status = dc.TRACKING_FILE_As;
 
                var results = loans.Join(status, sta => sta.Loan_ID, tr => tr.Loan_ID,
                  (tr, sta) => new { tr.Loan_ID, tr.f463_loan_status, tr.f450_loan_officer_code, tr.f2b1_last_name_buyer, tr.F430B1_dob_buyer, tr.f413_application_date, tr.f426_disbursement_date, tr.f7001_Buyer_1_First_and_Last_Name, tr.f13B1_B1_Curr_Street, tr.f14B1_B1_Curr_City, tr.f15B1_B1_Curr_St_Zip, tr.f440b1_Buyers_mailing_street_address, tr.f441b1_Buyers_mailing_city_State_zip, sta.f447b1_b1_email_address }).OrderBy(c => c.Loan_ID)
                  .Select(r => new { r.Loan_ID, r.f450_loan_officer_code, r.f463_loan_status, r.f2b1_last_name_buyer, r.F430B1_dob_buyer, r.f413_application_date, r.f426_disbursement_date, r.f7001_Buyer_1_First_and_Last_Name, r.f13B1_B1_Curr_Street, r.f14B1_B1_Curr_City, r.f15B1_B1_Curr_St_Zip, r.f440b1_Buyers_mailing_street_address, r.f441b1_Buyers_mailing_city_State_zip, r.f447b1_b1_email_address });
 
                if (!string.IsNullOrEmpty(cbLO.Text))
                {
                    results = results.Where(r => r.f450_loan_officer_code == cbLO.Text);
                }
                if (rbApplicationDate.Checked)
                    results = results.Where(c => c.f413_application_date >= dtpStart.Value.Date
                                                 & c.f413_application_date <= dtpEnd.Value.Date);
                if (rbDisbursementDate.Checked)
                    results = results.Where(c => c.f426_disbursement_date >= dtpStart.Value.Date
                                                 & c.f426_disbursement_date <= dtpEnd.Value.Date);
 
                if (ckStatus.Checked)
                    results = results.Where(c => c.f463_loan_status == cbStatus.Text);
 
                dataGridView1.DataSource = results;
                lblStatus.Text = string.Format("Record Count: {0:#,##0}", results.Count());
 
                SetColumns();
            }