Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
tinh cua » trinh cua, sinh cua, tinh chat
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
te sach » toc sach
va anh » van anh, va danh, va banh
va cau » van cau, va cac, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thuat sach) or (te sach)) ky nang ma hoa. hieu va cau truc ((va anh) OR (va hanh)) tinh cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (te sach)) ky nang ma hoa. hieu va cau truc ((va anh) OR (va hanh)) tinh cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sach) or (te sach)) ky nang ma hoa. hieu va cau truc ((va anh) OR (va hanh)) tinh cua tre*".