Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
viec bach » vien bach, viec ban, viec bao
bach tuoc » sach duoc, sach nuoc
van thanh » ban thanh, van tuan
tuoc van » luoc van, quoc van, thuoc von
thanh co » thanh do, thanh ca, thanh ho
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
co cua » con cua, ca cua, cong cua
o hoc » mo hoc, so hoc, y hoc

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 y nang ((o hoc) or (co hoc)). hieu viec bach tuoc van thanh co cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((o hoc) OR (co hoc)). hieu viec bach tuoc van thanh co cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((o hoc) or (co hoc)). hieu viec bach tuoc van thanh co cua tre*.