Perhaps you should try some spelling variations:
thien van » thi van
cua viet » ca viet, hoa viet, cua vat
nam thuc » nam thuoc, am thuc, nam thu
lang van » dang van, tang van, hoang van
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay
hieu va » lieu va, hieu qua
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 ky ((lang xa) or (lang van)) hoi. ((hieu va) or (thien van)) nam thuc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((lang xa) OR (lang van)) hoi. ((hieu va) OR (thien van)) nam thuc va hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((lang xa) or (lang van)) hoi. ((hieu va) or (thien van)) nam thuc va hanh vi cua viet*.