Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh tai » thanh hai, thanh toan, doanh tai
cau tren » cu tren, dau tren, ca tren
tu sach » thu sach, su sach, te sach
ty hang » ly hang, ty xang, thi hang
hang do » hang doi, dang do, hang di
hieu ve » hieu va, hieu van
cac dua » cach dua, cac qua, ca dua
sach ty » sach y, sach tu, sach thu
cua te » cua tu
do hoi » do choi, do hoai, do thoi

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 ty hang do hoi. hieu ve ((cac dua) or (cac du)) ban thanh tai ((cau tren) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty hang do hoi. hieu ve ((cac dua) OR (cac du)) ban thanh tai ((cau tren) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach ty hang do hoi. hieu ve ((cac dua) or (cac du)) ban thanh tai ((cau tren) or (cua te))*.