Perhaps you should try some spelling variations:
thanh tay » thanh tai, thanh toan, thanh thuy
khach ky » hanh ky, thanh ky
cap nuoc » dat nuoc
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
va hang » van hang, va nang, va lang
va cap » va cac, va dap, va cao
di cua » doi cua, de cua, do cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu ((khach ky) or (thanh tay)) tang xa hoi. hieu va cap nuoc va hang ((di cua) OR (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((khach ky) OR (thanh tay)) tang xa hoi. hieu va cap nuoc va hang ((di cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((khach ky) or (thanh tay)) tang xa hoi. hieu va cap nuoc va hang ((di cua) OR (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: vu ((khach ky) or (thanh tay)) tang xa hoi. hieu va cap nuoc va hang ((di cua) OR (dai cua)) tre*.