Perhaps you should try some spelling variations:
van nang » van quang, van ban, van dong
hieu van » hieu va, thien van, lieu va
thuc dan » hoc dan, thuc vat
cua viet » ca viet, hoa viet, cua vat
vu sach » su sach, vu khach
nang xa » nang x, lang xa, nang ma
van am » van nam, van lam, van dam
vi cua » vai cua, di cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sach) OR (vu bach)) van nang xa hoi. hieu van am ((thuc hanh) or (thuc dan)) hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (vu bach)) van nang xa hoi. hieu van am ((thuc hanh) OR (thuc dan)) hanh vi cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) OR (vu bach)) van nang xa hoi. hieu van am ((thuc hanh) or (thuc dan)) hanh vi cua viet*".