Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
khanh thi » nhanh thi, khanh thu, nhanh thai
van khanh » van thanh, van hanh, van anh
vien cac » vien bach, vien dai, vien da
thi cuc » tai cuc
luc van » luoc van, luu van, duc van
cac luc » cau luc, coc luc, cac nuoc
tu sach » thu sach, su sach, te sach
cuc tre » duc tre, cua tre, cuu tre
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
o hai » co hai, so hai, o lai
o hoi » co hoi, o hoc, o hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach v nang ((o hoi) or (o hai)). hieu vien cac luc van khanh thi cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach v nang ((o hoi) OR (o hai)). hieu vien cac luc van khanh thi cuc tre.
• Adding a wildcard symbol may retrieve word variants: tu sach v nang ((o hoi) or (o hai)). hieu vien cac luc van khanh thi cuc tre*.