Perhaps you should try some spelling variations:
ky tang » ky nang, ky dang, kho tang
so sai » so dai, so hai, do sai
vi hoc » li hoc, va hoc
dan vi » doan vi, don vi, dan va
va dan » ca dan, va dao, va dau
tuc va » thuc va, truc va, tuc xa
ve cac » va cac, vien cac
sai ky » sac ky
ve cam » ve cham, va cam, ve cai
ma hoi » mai hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sai ky tang ((ma hoi) or (xa hoi)). hieu ((ve cam) OR (ve cac)) tuc va dan vi hoc (hien or tien)~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sai ky tang ((ma hoi) OR (xa hoi)). hieu ((ve cam) OR (ve cac)) tuc va dan vi hoc (hien OR tien).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sai ky tang ((ma hoi) or (xa hoi)). hieu ((ve cam) OR (ve cac)) tuc va dan vi hoc (hien or tien)".
• Adding a wildcard symbol may retrieve word variants: so sai ky tang ((ma hoi) or (xa hoi)). hieu ((ve cam) OR (ve cac)) tuc va dan vi hoc (hien or tien)*.