Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
van thanh » ban thanh, van tuan
van khanh » van hanh, van anh, van phan
thai van » thi van, thanh van, thai vung
vien cac » vien bach, vien dai, vien da
van tren » van tien, quan tren, van trung
sach ty » sach y, sach tu, sach thu
cac xuc » cam xuc, cac nuoc, chat xuc
ty nang » ky nang, ty xang, ty hang
te sach » toc sach
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: te sach ty nang ((o hoi) or (o hai)). hieu vien cac xuc ((van khanh) or (van thanh)) thai van tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((o hoi) OR (o hai)). hieu vien cac xuc ((van khanh) OR (van thanh)) thai van tren.
• Adding a wildcard symbol may retrieve word variants: te sach ty nang ((o hoi) or (o hai)). hieu vien cac xuc ((van khanh) or (van thanh)) thai van tren*.