Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
van cac » van hac, van cau, van bac
cua tre » cuu tre, cua triet, dua tren
dai ban » dai han, tai ban, di ban
cac dai » cac dan, cac bai, can dai
sach ly » sach y, sach ty, sach hay
sach lo » sach dao, sach doi, sach hoi
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ly) OR (sach lo)) nang x hoi. hieu van cac dai ban thanh dai ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ly) OR (sach lo)) nang x hoi. hieu van cac dai ban thanh dai ((cua tre) or (cua te))~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ly) OR (sach lo)) nang x hoi. hieu van cac dai ban thanh dai ((cua tre) or (cua te))*.