Combination

Question

Hey...i want to ask who know how to do the Combination? 
For example,

my text file content:
1 2 3 4 5
2 3 4
1 2 4 5
.....

How i do the combination to like this:

{1,2}
{1,2,3}
{1,2,3,4}
......
I have been try many times, but still cannot get it...hope someone can help me...thanks so much...