Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
dau luc » cau luc, dau luan, dau nuoc
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
ma hoi » xa hoi, ma hoa, me hoi
va dau » va dao
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (tu cac)) ky nang ((ma hoi) or (mai hoi)). hieu va dau luc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (tu cac)) ky nang ((ma hoi) OR (mai hoi)). hieu va dau luc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (tu cac)) ky nang ((ma hoi) or (mai hoi)). hieu va dau luc va hanh vi cua tre*.