Missak,

Depends on what you are wanting to do.

If you just want to export 3 different movies based on your splits, just highlight the section you want.

Then in the Export dialog make sure you check the box that says something similar to "export selection only".

Or, if you want to save three different time lines projects save your current one 2 times each with a different name. Close out and then open each one and delete the material you don't want an save.

Or, there is a feature called takes.  i don't use it because I found it too confusing.  Look it up in the pdf manual and see if that does what you want.  Basically saving a selected area as a take allows you to call it into another time line project.

David