Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hieu ve » hieu va
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
va dinh » van dinh, va kinh, va tinh
dai su » dai sua, dai so, lai su
dan su » dang su
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang x hoi. ((hieu ve) or (hieu van)) am thuc va dinh ((dai su) OR (dan su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang x hoi. ((hieu ve) OR (hieu van)) am thuc va dinh ((dai su) OR (dan su)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang x hoi. ((hieu ve) or (hieu van)) am thuc va dinh ((dai su) OR (dan su)) triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang x hoi. ((hieu ve) or (hieu van)) am thuc va dinh ((dai su) OR (dan su)) triet*.