From The Document Foundation Wiki
Complete the following steps.
- Choose Send merged document as E-Mail. The To area indicates E-mail address (if you enter something else, like Name or Surname, the send operation will fail).
- Choose the setting to send an attached file or to insert the text into the body of the e-mail.
Clicking Properties opens a window into which you can enter the text of the message.
- The window that opens allows you to check that all the e-mails have been sent successfully.