Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cham hoc » cham soc, chat hoc, cham hoi
danh vai » danh sai, danh va, doanh van
su sach » so sach, vu sach
va cham » va chat, va tham
va danh » va dinh, va dan, va hanh
cua tre » cua te, cuu tre, dua tren
y tang » ky tang, 7 tang, 5 tang
ma hoi » mai hoi, xa hoi, ma hoa

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: su sach ((y tang) OR (6 tang)) ma hoi. lieu va cham hoc va danh vai ((cua tre) OR (cua triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y tang) or (6 tang)) ma hoi. lieu va cham hoc va danh vai ((cua tre) OR (cua triet))~".
• Adding a wildcard symbol may retrieve word variants: su sach ((y tang) or (6 tang)) ma hoi. lieu va cham hoc va danh vai ((cua tre) OR (cua triet))*.