Perhaps you should try some spelling variations:
thien van » thi van
thanh tay » thanh tai, thanh toan, thanh thuy
hanh tai » thanh tai, hang tai, han tai
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
thanh ky » hanh ky, than ky, thanh huy
tai cua » thai cua, tai cuc, tri cua
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
van cac » van hac, van cau, van bac
xay hoi » tay hoi, cay phoi, gay thoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu ((thanh ky) OR (thanh tay)) dang ((xay hoi) or (xa hoi)). thien van cac nuoc va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((thanh ky) OR (thanh tay)) dang ((xay hoi) OR (xa hoi)). thien van cac nuoc va hanh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((thanh ky) OR (thanh tay)) dang ((xay hoi) or (xa hoi)). thien van cac nuoc va hanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: vu ((thanh ky) OR (thanh tay)) dang ((xay hoi) or (xa hoi)). thien van cac nuoc va hanh tai cua tre*.