Hi Alain
If you mean that you have for example 3 songs (a medley) on 1 sequencer file and you wish to save as three seperate songs. You could edit the sequencer file and delete/erase all measures except those containing song 1 then save as a new file. Then back to the original sequencer file and repeat deleting/erasing all measure except those containing song 2 etc. I know it sounds a bit long winded and no doubt someone will come up with a much short method
Anyway, good luck with it
John