There are a couple of ways to view invoices that are matched to POs
Using Advanced Search
Select 'Advanced Search' at the top of Beanworks.
Under 'Select Filter', choose 'Matched to PO' (in the invoices module) or 'Matched Inv' (in the PO module).
Using Actions Icon
While in the grid view of the Invoice or Purchase Order module (in any step in the workflow besides Create).
Select the PO Match icon.