For small orders the items will be visible on the right side of the scan & pack interface. For large orders the items will exceed the available space.
You can view a list of all of the orders activity, including each of the items that have been scanned by clicking on the order number where it appears in the center of the Scan and Pack interface:
...and then clicking on the Activity/Exceptions tab:
The activity list can be searched using Ctrl-f (Command F on Mac). This makes it easy to find a specific SKU.
It's also possible to Select All or Part of the Activity log and print it using ctrl-p (command p on mac). This same method can be used to save a pdf of the items if you print to pdf.