Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
hanh lai » hanh lam, hanh tai, thanh lap
cac tuc » cac toc, cac tu, cac tac
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hieu ve » hieu van
hang xa » hoang xa, hang va, hang ca
ty hang » ly hang, ty xang, thi hang
hieu va » lieu va, hieu qua
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty hang xa hoi. ((hieu ve) or (hieu va)) cac tuc va hanh lai ((cua tre) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty hang xa hoi. ((hieu ve) OR (hieu va)) cac tuc va hanh lai ((cua tre) OR (dau tren)).
• Adding a wildcard symbol may retrieve word variants: su sach ty hang xa hoi. ((hieu ve) or (hieu va)) cac tuc va hanh lai ((cua tre) or (dau tren))*.