Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
thanh dai » thanh hai, thanh tai, thanh dat
hieu van » hieu va, thien van, lieu va
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ty hang » ly hang, ty xang, thi hang
van cac » van hac, van cau, van bac
cac duc » cac du, cao duc, cac dac
cua tre » cua te, cuu tre, cua triet
hang x » nang x, hoang xa, chang xu
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty hang x hoi. hieu van cac duc va ((thanh dai) or (thanh toan)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty hang x hoi. hieu van cac duc va ((thanh dai) OR (thanh toan)) cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ty hang x hoi. hieu van cac duc va ((thanh dai) or (thanh toan)) cua tre*.