Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
viec cac » vien cac, viec cua, viec lam
te sach » toc sach
lua tre » cua tre, dua tren, luat tri
doan vi » don vi, doan thi, doan van
luy tre » luyen tre
cac luc » cau luc, coc luc, cac nuoc
luc va » duc va, tuc va, loc va
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
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 viec cac luc va ((doan vi) OR (doan va)) ((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 viec cac luc va ((doan vi) OR (doan va)) ((lua tre) OR (luy tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang o hoi. hieu viec cac luc va ((doan vi) OR (doan va)) ((lua tre) or (luy tre))".
• Adding a wildcard symbol may retrieve word variants: te sach y nang o hoi. hieu viec cac luc va ((doan vi) OR (doan va)) ((lua tre) or (luy tre))*.