It might help to do a quick search on Sajha regarding this. Almost every other week we see question like this.

Now, one time rejection shouldn't deter them from reapplying. However, make sure you show some good reason as to why they will come back to Nepal. If they have a job back home, that helps. Otherwise, some family ties/responsibility might help. You have to show as much money/property as you can. Get the property evaluated by your town office.