Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
chet nuoc » chet duoc, che duoc, chua nuoc
su triet » su viet, su tien, ve triet
hieu va » lieu va, hieu qua
te sach » toc sach
va chet » va chiet, va che, va chat
sach v » sach va, sach y, sach 2
ma hoi » mai hoi, ma hoa, me hoi
va dau » va dao
dau vi » dau ve, dau va, dat vi
v nang » va nang, vu nang, van nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach v nang ((ma hoi) OR (xa hoi)). hieu va chet nuoc va dau vi ((cua triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach v nang ((ma hoi) OR (xa hoi)). hieu va chet nuoc va dau vi ((cua triet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v nang ((ma hoi) OR (xa hoi)). hieu va chet nuoc va dau vi ((cua triet) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: te sach v nang ((ma hoi) OR (xa hoi)). hieu va chet nuoc va dau vi ((cua triet) or (su triet))*.