Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
hanh tai » thanh tai, hang tai, han tai
tu sach » thu sach, su sach, te sach
va cham » va chat, va tham
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
xuc va » tuc va, luc va, xac va
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: tu sach y nang o hoi. hieu va cham ((xuc va) OR (duc va)) hanh tai ((cua triet) OR (va triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang o hoi. hieu va cham ((xuc va) or (duc va)) hanh tai ((cua triet) OR (va triet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang o hoi. hieu va cham ((xuc va) or (duc va)) hanh tai ((cua triet) OR (va triet))*.