Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
luoc van » luoc can, luoc va, luot van
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
luc van » luu van, duc van, luc va
cua tre » cua te, cuu tre, dua tren
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
va cam » va cham, va cac, va cao
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang o hoi. hieu va cam ((luc van) OR (luoc van)) thanh san ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang o hoi. hieu va cam ((luc van) OR (luoc van)) thanh san ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang o hoi. hieu va cam ((luc van) OR (luoc van)) thanh san ((cua tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach y nang o hoi. hieu va cam ((luc van) OR (luoc van)) thanh san ((cua tre) or (cua triet))*.