How to burn with multisession?

Hi,
I want to burn a DVD disc for serveral times.
How to set the write paras?

When I set “–close-session”,I can reburn the DVD disc.
But I can’t see the former information I’ve burned though the disc is acturelly used.

First ,I’m shamed to have asked the question in such a bad way.
Second,I solved the problem by re-create the file system of burned and under- burning on the disc.