Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh dao » lanh dao, thanh dat, thanh dam
hanh dai » hanh tai, vanh dai, thanh dat
dang cay » dang xay, dang ca, dang cac
cay phoi » cap phoi, tay hoi, cay cho
sach thu » sach thue, sach thieu, sach tham
cua tre » cua te, cuu tre, cua triet
nam tuc » nam thuc, nam truc, nam tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach thu) or (sach y)) dang cay phoi. hieu van nam tuc xa ((hanh dai) OR (hanh dao)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thu) OR (sach y)) dang cay phoi. hieu van nam tuc xa ((hanh dai) OR (hanh dao)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach thu) or (sach y)) dang cay phoi. hieu van nam tuc xa ((hanh dai) OR (hanh dao)) cua tre*".