Perhaps you should try some spelling variations:
chat thuc » thuat thuc, nhan thuc, chat huu
thu sach » tu sach, thuat sach, thuoc sach
hieu van » thien van, lieu va, hieu ve
danh sai » dung sai, danh bat, danh dau
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va danh » va dinh, va dan, va hanh
sai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet

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 xa hoi. ((hieu van) OR (hieu va)) ((chat thuc) or (chat thai)) va danh sai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. ((hieu van) OR (hieu va)) ((chat thuc) OR (chat thai)) va danh sai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang xa hoi. ((hieu van) OR (hieu va)) ((chat thuc) or (chat thai)) va danh sai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. ((hieu van) OR (hieu va)) ((chat thuc) or (chat thai)) va danh sai cua tre*.