Perhaps you should try some spelling variations:
chau doc » chat doc, cau do, phau hoc
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
va chau » va chat, va cau, va cham
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
tu ban » thu ban, te ban
ban ky » van ky, dan ky
doc va » duoc va, hoc va, duc va
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ban ky tang xa hoi. hieu va chau doc va dan vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ban ky tang xa hoi. hieu va chau doc va dan vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu ban ky tang xa hoi. hieu va chau doc va dan vi ((cua tre) or (cuu tre))*.