Perhaps you should try some spelling variations:
khoa tang » khoa dang, khoa tieng, khoa trung
thu bach » thi bach, thu sach, thu hoach
hanh dan » thanh dan, hanh san, canh dan
kho tang » cao tang
cham tuc » nham thuc, pham thuc, tham thuc
va hanh » van hanh, va thanh, va danh
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
dan cua » dan ca, ban cua, dai cua
mai hoi » mai khoi, dai hoi, lai hoi
ma hoi » xa hoi, ma hoa, me hoi
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu bach ((khoa tang) OR (kho tang)) ((ma hoi) or (mai hoi)). hieu ve cham tuc va hanh dan cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu bach ((khoa tang) OR (kho tang)) ((ma hoi) OR (mai hoi)). hieu ve cham tuc va hanh dan cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu bach ((khoa tang) OR (kho tang)) ((ma hoi) or (mai hoi)). hieu ve cham tuc va hanh dan cua vat".
• Adding a wildcard symbol may retrieve word variants: thu bach ((khoa tang) OR (kho tang)) ((ma hoi) or (mai hoi)). hieu ve cham tuc va hanh dan cua vat*.