Perhaps you should try some spelling variations:
doanh vai » doanh tai, doanh va, doanh van
van doanh » toan doanh, van dong, van thanh
hieu viec » nhieu viec, hieu ve, sieu viet
viec cac » vien cac, viec cua, viec lam
dang xay » van xay
dang van » hoang van, hang va
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
lang xa » lang ha, lang van
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
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 xa) or (((dang xay) OR (dang van)))) hoi. hieu viec cac lo van doanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((lang xa) OR (((dang xay) OR (dang van)))) hoi. hieu viec cac lo van doanh vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((lang xa) or (((dang xay) OR (dang van)))) hoi. hieu viec cac lo van doanh vai cua tre*".