Select one or more emails and click the "View email(s)" button in the ribbon or select the option "View email(s)" the context menu of one of the selected emails. This opens a dialog window with the preview.
Use the "previous" or "next" buttons to view adjacent emails or enter the number to jump to a specific email.
To view all emails simply select the "View email(s)" button in the ribbon.
NB: the tool uses the column filtering values and sort order to select the identical set of emails.