Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
toan quy » tran quy, tan quy, toan quyet
dang xay » van xay
dang van » hoang van, hang va
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
ve chat » va chat, van chat
sach ky » sac ky, sach y, sach ty
quy tre » luy tre

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 xay) OR (dang van)) hoi. hieu ve chat ((tuc xa) or (thuc va)) thanh toan quy tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((dang xay) OR (dang van)) hoi. hieu ve chat ((tuc xa) OR (thuc va)) thanh toan quy tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((dang xay) OR (dang van)) hoi. hieu ve chat ((tuc xa) or (thuc va)) thanh toan quy tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((dang xay) OR (dang van)) hoi. hieu ve chat ((tuc xa) or (thuc va)) thanh toan quy tre*.