Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
toc sach » hoc sach, doc sach, thuoc sach
minh vai » minh va, minh hai, minh ai
vien dai » hien dai
vai cua » dai cua, hai cua, lai cua
luc van » luoc van, luu van, duc van
dai luc » dai luoc, dai luan, dai thuc
cua tre » cua te, cuu tre, cua triet
lai hoi » dai hoi, lai hoa, lai roi
mai hoi » mai khoi, dai hoi, mai doi
ly nang » ky nang, ly hang, ly vang

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) OR (toc sach)) ly nang ((mai hoi) or (lai hoi)). hieu vien dai luc van minh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ly nang ((mai hoi) OR (lai hoi)). hieu vien dai luc van minh vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ly nang ((mai hoi) or (lai hoi)). hieu vien dai luc van minh vai cua tre*".