Record not found

When I locate the TAdoTables I reciave error "Record not Found"
insted of "false".
found1 := tblDokumenti.Locate('VID_DOKUMENT',myInteger,[]);
Is it possible the reason of the problem to be the filter.
I use OnFilterRecord event to filter on Month of date.

I'm using:
Access 2000
D5 update pack 2
ADOExpress upgrade pack 2

Can anyone help me with this Please.
Thanks in advance.

Ivan