Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
hieu cua » hieu qua, dieu cua, bieu cua
cac quoc » cac nuoc, cac cuoc, cao quoc
van hanh » ban hanh, van anh, van ban
dang xay » dang van, van xay
hoi cua » hoi chuc
te sach » toc sach
sach ty » sach y, sach tu, sach thu
lang xa » lang ha, lang van
cua te » cua tu

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 ((lang xa) or (dang xay)) hoi. hieu cua cac quoc ((van hanh) or (van thanh)) hoi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((lang xa) OR (dang xay)) hoi. hieu cua cac quoc ((van hanh) OR (van thanh)) hoi cua te.
• Adding a wildcard symbol may retrieve word variants: te sach ty ((lang xa) or (dang xay)) hoi. hieu cua cac quoc ((van hanh) or (van thanh)) hoi cua te*.