Perhaps you should try some spelling variations:
van doanh » toan doanh, van dong, van thanh
hieu viec » nhieu viec, hieu ve, sieu viet
viec cac » vien cac, viec cua, viec lam
tu sach » thu sach, te sach, tu cach
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
ky lang » ky nang, ky dang, ky tang
su sach » so sach, vu sach
ha hoi » hoa hoi, xa hoi, va hoi
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) OR (su sach)) ky lang ((ha hoi) or (ha noi)). hieu viec cac lo van doanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky lang ((ha hoi) OR (ha noi)). hieu viec cac lo van doanh tai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) ky lang ((ha hoi) or (ha noi)). hieu viec cac lo van doanh tai cua tre*".