Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
ban thanh » ban hanh, ban hang
dang khai » dang khoi, dang hai, quang khai
toan cua » than cua, tan cua, doanh cua
dang mai » dang hai, dang mau, dang bai
tu sach » thu sach, su sach, te sach
dua ban » dia ban, cua ban, qua ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
va cao » va cac, va co, va dao
va ca » va cac, va cai, va cau

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 ky ((dang mai) or (dang khai)) hoa. hieu ((va ca) OR (va cao)) dua ban thanh toan cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((dang mai) OR (dang khai)) hoa. hieu ((va ca) OR (va cao)) dua ban thanh toan cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((dang mai) or (dang khai)) hoa. hieu ((va ca) OR (va cao)) dua ban thanh toan cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((dang mai) or (dang khai)) hoa. hieu ((va ca) OR (va cao)) dua ban thanh toan cua tre*.