Perhaps you should try some spelling variations:
hanh gian » thanh gian, thanh giang, manh giang
gian cua » gian xu, ban cua
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cuu tre, cua triet
ma hoi » xa hoi, ma hoa, me hoi
bai bo » bac bo, ban bo, bai mo
bo va » bao va, do va, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sanh) OR (do sanh)) ky nang ((ma hoi) or (mai hoi)). hieu va bai bo va hanh gian cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sanh) OR (do sanh)) ky nang ((ma hoi) OR (mai hoi)). hieu va bai bo va hanh gian cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sanh) OR (do sanh)) ky nang ((ma hoi) or (mai hoi)). hieu va bai bo va hanh gian cua tre".
• Adding a wildcard symbol may retrieve word variants: ((so sanh) OR (do sanh)) ky nang ((ma hoi) or (mai hoi)). hieu va bai bo va hanh gian cua tre*.