Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
san thanh » ban thanh, van thanh, son thanh
toan cua » than cua, tan cua, doanh cua
sach ky » sach y, sach ty, sach kem
cac chu » cac thu, cac che, cac khu
cac cuu » cap cuu, cac cau, cac cua
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky

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) or (sac ky)) nang xa hoi. hieu ve ((cac cuu) OR (cac chu)) san thanh toan cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang xa hoi. hieu ve ((cac cuu) OR (cac chu)) san thanh toan cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang xa hoi. hieu ve ((cac cuu) OR (cac chu)) san thanh toan cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang xa hoi. hieu ve ((cac cuu) OR (cac chu)) san thanh toan cua tre*.