We are using Google Apps for sending mail. I have to convert all doc file in ms office format.
I’m not sure exactly what your question is, and the lack of punctuation doesn’t help.
How do you send send documents through gmail? Attach them (see gmail help).
“We are using Google Apps”… How is this relevant to LibreOffice, then? (see Google Apps help)
Need to convert documents? From what format, into what format, for what reason, and individually or batched?