Perhaps you should try some spelling variations:
khach ky » hanh ky
thanh ky » hanh ky, than ky, thanh tay
hieu cua » hieu qua, dieu cua, bieu cua
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
tang xa » trang xa, tang ma, lang xa
va hang » van hang, va nang, va lang
hang vi » hang va, hanh vi, hang di
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di 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 ky)) tang xa hoi. hieu cua cac nuoc va hang vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((khach ky) OR (thanh ky)) tang xa hoi. hieu cua cac nuoc va hang vi cua tre.
• Adding a wildcard symbol may retrieve word variants: vu ((khach ky) or (thanh ky)) tang xa hoi. hieu cua cac nuoc va hang vi cua tre*.