Perhaps start with a simpler filter, like just credit notes, to limit the number of records. Ensure that columns for Date, Category, Item # and Line Type are selected for the view (at least for now) since those are the other fields referenced in your filter. When that filter is selected, find one of your credit notes that was not based on an order. If you can't find any, then that would explain why your complete filter doesn't. If you can find at least one, then you can investigate the other 4 field values to see why it isn't being selected from your complete filter.