Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va hanh » van hanh, va thanh, va danh
dau cua » dai cua, day cua, cau cua
cao hoi » cau hoi, co hoi, cao hoc
hieu vu » hieu va, hieu ve, hieu su
va dan » ca dan, va dao, va dau
vu cam » vu cham, vu cao, va cam
cua te » cua tu

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 (toc sach)) ky nang cao hoi. hieu vu cam xuc ((va hanh) or (va dan)) dau cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang cao hoi. hieu vu cam xuc ((va hanh) OR (va dan)) dau cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky nang cao hoi. hieu vu cam xuc ((va hanh) or (va dan)) dau cua te".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ky nang cao hoi. hieu vu cam xuc ((va hanh) or (va dan)) dau cua te*.