Datagrid wont display data when sql contains where clause

I am working on a windows forms application vb.net / Access . I have a form which contains a set of text boxes for search criteria, a command button which contains the code for displaying the data and a datagrid. The datagrid displays just fine when the sql does not contain where clause. Button_click contains the following: The sql is as follows: searchstr = "SELECT TransNo, [Authorization], RDM, ItemDesc, TransDate, Vendor, HoldersName, UnitCost, TotalAmt, Credit, Memo, PKey From PCardLog where " & UCase(searchstr) & " and ((RDM Is Null) Or (RDM In ('M','D'))) order by Pkey DESC" ' Dim strSQL As String = searchstr Dim dsUnRec As New DataSet() dsUnRec = GetDataSet(strSQL, "UnRec") DataGrid1.DataSource = dsUnRec.Tables("UnRec") Private Function GetDataSet(ByVal sql As String, ByVal dstab As String) As DataSet Try Cmd.Connection = Conn 'Conn declared in public module Cmd.CommandText = sql Conn.Open() Dim adapter As New OleDbDataAdapter() adapter.SelectCommand = Cmd Dim ds As New DataSet(dstab) adapter.Fill(ds, dstab) Return ds Catch err As Exception lblstatus.Text = err.Message Finally Conn.Close() End Try End Function I dont get an error while running this. By the way, I tried debug.writeline to extract the sql and try on access database It returns the results just fine. Can anyone please help?