Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
hieu van » hieu va, thien van, lieu va
va thieu » va thiet, va hieu, va tieu
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va
thuc va » thuc vat, thuc dan, thuc day
van mai » van hai, van ai, ban mai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky lang xa hoi. ((hieu ve) or (hieu van)) nham thuc va van mai va thieu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky lang xa hoi. ((hieu ve) OR (hieu van)) nham thuc va van mai va thieu.
• Adding a wildcard symbol may retrieve word variants: su sach ky lang xa hoi. ((hieu ve) or (hieu van)) nham thuc va van mai va thieu*.