Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
cham luc » cham soc, cham cuu, chat lua
nhan luc » nang luc
hanh doi » thanh doi, hanh noi, hang doi
so sach » so sanh, bo sach, co sach
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach ty
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.

• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang o hoi. hieu qua ((cham luc) OR (nhan luc)) va hanh doi ((cau tren) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang o hoi. hieu qua ((cham luc) OR (nhan luc)) va hanh doi ((cau tren) or (cua te))~".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang o hoi. hieu qua ((cham luc) OR (nhan luc)) va hanh doi ((cau tren) or (cua te))*.