Perhaps you should try some spelling variations:
khach ky » hanh ky
thanh ky » hanh ky, than ky, thanh tay
cac thoi » cac toi, cac hop, cac tro
hieu van » hieu va, thien van, lieu va
tinh vi » trinh vi, tinh voi, tinh va
va tinh » may tinh
cac toc » cac toi, cac nuoc
tang xa » trang xa, tang ma, lang xa
luu tre » luu tru, cuu tre, luy tre
vi luu » vi lua

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 van ((cac toc) or (cac thoi)) va tinh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((khach ky) OR (thanh ky)) tang xa hoi. hieu van ((cac toc) OR (cac thoi)) va tinh vi luu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((khach ky) OR (thanh ky)) tang xa hoi. hieu van ((cac toc) or (cac thoi)) va tinh vi luu tre*".