Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
cham duc » pham duc, cham soc, pham duy
may thoi » gay thoi, may thi, tay thoi
hang dau » hang va, hang tai
va hang » van hang, va nang, va lang
te sach » toc sach
hieu ve » hieu va, hieu van
may hoi » tay hoi, mai hoi, may hmi
ve cham » va cham, ve chat, vu cham
y mang » cay mang

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 y mang ((may hoi) or (may thoi)). hieu ve cham duc va hang dau ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y mang ((may hoi) OR (may thoi)). hieu ve cham duc va hang dau ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y mang ((may hoi) or (may thoi)). hieu ve cham duc va hang dau ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: te sach y mang ((may hoi) or (may thoi)). hieu ve cham duc va hang dau ((cua triet) OR (va triet))*.