Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
viec dan » viec dang, viec ban, viec dat
dan thuc » dan toc, am thuc
thuc cao » thuoc cao, thuc co, thuc can
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ty hang » ly hang, ty xang, thi hang
doan vi » doan va, doan thi, doan van
cua tre » cua te, cuu tre, cua triet
hang x » nang x, hoang xa, chang xu
x hoi » xa hoi, o hoi, x ho

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 hang x hoi. nhieu viec dan thuc cao ((doan vi) or (don vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty hang x hoi. nhieu viec dan thuc cao ((doan vi) OR (don vi)) cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ty hang x hoi. nhieu viec dan thuc cao ((doan vi) or (don vi)) cua tre*.