Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va triet » va trien, ve triet, cua triet
hanh dai » hanh tai, hanh dao, vanh dai
cham luc » cham soc, nhan luc, cham cuu
va hanh » van hanh, va thanh, va danh
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
cao hoi » cau hoi, co hoi, cao hoc
da nang » cam nang, kha nang, cao nang
luc va » duc va, tuc va, loc va
v nang » va nang, vu nang, van nang
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((v nang) or (da nang)) cao hoi. hieu ve cham luc va hanh dai ((va triet) OR (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((v nang) OR (da nang)) cao hoi. hieu ve cham luc va hanh dai ((va triet) OR (va thiet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((v nang) or (da nang)) cao hoi. hieu ve cham luc va hanh dai ((va triet) OR (va thiet))".
• Adding a wildcard symbol may retrieve word variants: toc sach ((v nang) or (da nang)) cao hoi. hieu ve cham luc va hanh dai ((va triet) OR (va thiet))*.