Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, hieu ve
danh vai » danh sai, danh va, doanh van
vai cua » dai cua, hai cua, lai cua
va danh » va dinh, va dan, va hanh
lam tuc » lam thuoc, lam truoc, luat tuc
te sach » toc sach
tuc va » thuc va, truc va, tuc xa
nang o » nang co, nang ho, nang ro
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (thuoc sach)) ky nang o hoi. ((hieu van) OR (lieu va)) lam tuc va danh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (thuoc sach)) ky nang o hoi. ((hieu van) OR (lieu va)) lam tuc va danh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (thuoc sach)) ky nang o hoi. ((hieu van) OR (lieu va)) lam tuc va danh vai cua te".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (thuoc sach)) ky nang o hoi. ((hieu van) OR (lieu va)) lam tuc va danh vai cua te*.