Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
dua tren » dung tren
te sach » toc sach
van cac » van hac, van cau, van bac
cac xuc » cam xuc, cac nuoc, chat xuc
y nang » ky nang, ly nang, v nang
xuc va » duc va, tuc va, luc va
va don » va dong, va doc, va do
vi dua » vi du, vi dum, vi lua
x hoi » xa hoi, x ho
o hoi » co hoi, o hoc, o hai

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((((x hoi) OR (5 hoi))) OR (o hoi)). hieu van cac xuc va don vi dua tren~.
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((((x hoi) or (5 hoi))) or (o hoi)). hieu van cac xuc va don vi dua tren*.