Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
te sach » toc sach
cac luc » cau luc, coc luc, cac nuoc
va doan » va doanh, van doan, va dan
doan vi » doan va, don vi, doan thi
lua tre » cua tre, dua tren, luat tri
luy tre » luyen tre
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
luc va » duc va, tuc va, loc va
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y nang o hoi. hieu vien cac luc va doan vi ((lua tre) or (luy tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang o hoi. hieu vien cac luc va doan vi ((lua tre) OR (luy tre)).
• Adding a wildcard symbol may retrieve word variants: te sach y nang o hoi. hieu vien cac luc va doan vi ((lua tre) or (luy tre))*.