Invoice Search by InternalId

After uploading an invoice, I would like to then retrieve that invoice by the InternalId for the invoice. I am trying the following but it returns 0 records.


                Dim tSearch As TransactionSearch = New TransactionSearch
                Dim tSearchBasic As TransactionSearchBasic = New TransactionSearchBasic
                Dim tInvoice As RecordRef() = New RecordRef(0) {}
                tInvoice(0) = New RecordRef
                tInvoice(0).internalId = 111081
                Dim tInvoiceSearch As New SearchMultiSelectField
                tInvoiceSearch.operator = SearchMultiSelectFieldOperator.anyOf
                tInvoiceSearch.searchValue = tInvoice

                tSearchBasic.internalId = tInvoiceSearch

                tSearch.basic = tSearchBasic
                Dim tResponse As SearchResult = service.search(tSearch)




Any suggestions?