Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
van doanh » toan doanh, van dong, van thanh
viec cac » vien cac, viec cua, viec lam
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
ha hoi » hoa hoi, va hoi, ha hoa
cac lo » cac lop, cac co, cac bo
lo van » le van, vo van, so van

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 ky lang ((((ha hoi) OR (xa hoi))) or (ha noi)). nhieu viec cac lo van doanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang ((((ha hoi) OR (xa hoi))) OR (ha noi)). nhieu viec cac lo van doanh tai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang ((((ha hoi) OR (xa hoi))) or (ha noi)). nhieu viec cac lo van doanh tai cua tre*".