Perhaps you should try some spelling variations:
dong cua » dung cua, cong cua, huong cua
cac tac » cac toc, cac bac, cac dac
doi cua » dai cua, hoi cua
xa nang » da nang, va nang, xa nong
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cac tuc » cac toc, cac tu, cac nuoc
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang

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 hoi. hieu ve ((cac tuc) or (cac tac)) xa nang ((doi cua) OR (dong cua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang xa hoi. hieu ve ((cac tuc) OR (cac tac)) xa nang ((doi cua) OR (dong cua)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang xa hoi. hieu ve ((cac tuc) or (cac tac)) xa nang ((doi cua) OR (dong cua)) viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. hieu ve ((cac tuc) or (cac tac)) xa nang ((doi cua) OR (dong cua)) viet*.