it should be like two semester in a college .. . so that way  .. u can  apply for work permit trough the  reason of economic hardship . ..  i had applied twice and got twice ..and soon  to be apply one ... cause two had already expired . ..   go to the international student advisor ... and ask him that u wanna  apply for  work permit .. . mentioning ur parents are  having hard time to support you.. . he will give u a form ..and u need to  write a letter one by yourself ..and  another  by ur  sponser ..  and  it would be better if u submit  the proof  of nepal economic crisis and the problem nepal facing  these days  .... Print some news like terai closed for 14th days, petroleum products shortage in nepal .. ..   inorder to have a proof in which ur parents are unabale to support u.