Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
tai cuu » tai cuc, tai buu, tai cua
qua ban » cua ban, qua quan
dua ban » dia ban, cua ban, mua ban
van cau » van dau, van hau, van chat
sach ly » sach y, sach lo, sach ty
ly nang » ky nang, ly hang, ly vang
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, me hoi

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 ly nang ((ma hoi) or (ma hoa)). hieu van cau ((dua ban) or (qua ban)) thanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ly nang ((ma hoi) OR (ma hoa)). hieu van cau ((dua ban) OR (qua ban)) thanh tai cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ly nang ((ma hoi) or (ma hoa)). hieu van cau ((dua ban) or (qua ban)) thanh tai cuu tre*.