Perhaps you should try some spelling variations:
kho tang » cao tang
hieu vu » hieu va, hieu ve, hieu su
dai hoi » dai hoc, dai hai
dai moi » doi moi
sac kho » suc khoe, cac khoi, dac khoa
vu chat » va chat, ve chat, du chat
truc va » thuc va, thuc vat, trung va
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua
tu sac » tu sach, tu cac, tu san
cua te » cua tu

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: tu sac kho tang ((dai hoi) OR (dai moi)). hieu vu chat ((truc va) OR (luc va)) hanh vi cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac kho tang ((dai hoi) OR (dai moi)). hieu vu chat ((truc va) or (luc va)) hanh vi cua te~".
• Adding a wildcard symbol may retrieve word variants: tu sac kho tang ((dai hoi) OR (dai moi)). hieu vu chat ((truc va) or (luc va)) hanh vi cua te*.