Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cau tren » cu tren, dau tren, ca tren
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cam duc » cam xuc, cao duc, nam duoc
va hanh » van hanh, va thanh, va danh
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: thu sach ky nang o hoi. hieu ve ((cam duc) OR (pham duc)) va hanh vi ((cua te) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang o hoi. hieu ve ((cam duc) OR (pham duc)) va hanh vi ((cua te) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang o hoi. hieu ve ((cam duc) OR (pham duc)) va hanh vi ((cua te) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang o hoi. hieu ve ((cam duc) OR (pham duc)) va hanh vi ((cua te) or (cau tren))*.