To save a specific mail, or a range of mails, right click the results window.
This presents a drop-down menu with the following options:
Open Message
Save Message(s)
Forward Message(s)
Export message list
As HTML document
As CSV document
As MS-Excel Document
Save Result List
Open Result List
Results can be saved by right-clicking. Note that a range of messages can be selected. Previously saved result list can be opened.
To search the mailboxes of specific accounts, click the Users tab. Then select the user or users to be included in your search.