Perhaps you should try some spelling variations:
van trinh » van thinh, van tinh, dan trinh
vien cac » vien bach, vien dai, vien da
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
cac luc » cau luc, coc luc, cac nuoc
luc van » luoc van, luu van, duc van
tu ban » thu ban, te ban
ban ky » van ky, dan ky

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 cac luc van trinh ((ve cac) or (vien cac)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ban ky tang xa hoi. hieu va cac luc van trinh ((ve cac) OR (vien cac)) tren.
• Adding a wildcard symbol may retrieve word variants: tu ban ky tang xa hoi. hieu va cac luc van trinh ((ve cac) or (vien cac)) tren*.