Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu luc » hieu luat, hieu qua
luc cham » luc tham, tuc cham, phuc cham
cham lao » chai lao, cham lai, cham vao
hanh vai » hanh vi, hanh va, hanh tai
cao hoi » cau hoi, co hoi, cao hoc
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
lao va » tao va, cao va, bao va
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: thuat sach y nang cao hoi. hieu luc cham lao va hanh vai ((cua te) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach y nang cao hoi. hieu luc cham lao va hanh vai ((cua te) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: thuat sach y nang cao hoi. hieu luc cham lao va hanh vai ((cua te) or (cuu tre))*.