Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
dang xay » dang van, van xay
van hanh » van thanh, ban hanh, van ban
viec cac » vien cac, viec cua, viec lam
va triet » va thiet, va trien, ve triet
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, lang van
cac tac » cac toc, cac bac, cac dac
van anh » van thanh, tuan anh, van minh
su sach » so sach, vu sach
vi va » vi van, vai va, vu va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((lang xa) OR (dang xay)) hoi. hieu viec cac tac ((van hanh) or (van anh)) vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((lang xa) OR (dang xay)) hoi. hieu viec cac tac ((van hanh) OR (van anh)) vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((lang xa) OR (dang xay)) hoi. hieu viec cac tac ((van hanh) or (van anh)) vi va triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((lang xa) OR (dang xay)) hoi. hieu viec cac tac ((van hanh) or (van anh)) vi va triet*.