On the top of the Invoices window are the Display Options. This allows you to filter your invoices to find the specific ones you are looking for. 
Display Options – Outstanding: From this drop-down menu, you can choose to display which invoices are displayed, either outstanding only, paid invoices only, or all invoices.
Display Options – Date Range: This is useful if you wish to see some of your ‘older’ outstanding invoices. You may wish to send a chaser letter to all invoices of a certain age, say 60 days or older for example. To do this, use date range to specify the date range you want.
Display Options – Search: You can type search criteria into this field, and it will restrict what records are shown in the window based on the search criteria.
Invoice Total: This will show you the Invoice Total based on your filters
Received: This will show you the Received amount based on your filters
Outstanding: This will show you the Outstanding amount based on your filters