Perhaps you should try some spelling variations:
danh xay » dang xay, manh xay, anh xay
danh van » doanh van, dang van, dinh van
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky danh » ky anh, ky dang
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » lieu va
duoc va » nuoc va, duoc ma, duong va
van cua » vang cua, ban cua, dan cua
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky danh xay hoi. ((hieu va) or (hieu qua)) lam ((duoc va) OR (duc va)) danh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky danh xay hoi. ((hieu va) OR (hieu qua)) lam ((duoc va) OR (duc va)) danh van cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky danh xay hoi. ((hieu va) or (hieu qua)) lam ((duoc va) OR (duc va)) danh van cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky danh xay hoi. ((hieu va) or (hieu qua)) lam ((duoc va) OR (duc va)) danh van cua tre*.