Perhaps you should try some spelling variations:
su viet » so viet
va danh » va dinh, va hanh, dia danh
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
hieu va » lieu va
dau su » dau tu, dan su, da su
va dan » ca dan, va dao, va dau
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
co tuc » co thuc, co tu, co toc

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky dang xa hoi. ((hieu va) or (hieu qua)) co tuc ((va danh) or (va dan)) dau su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky dang xa hoi. ((hieu va) OR (hieu qua)) co tuc ((va danh) OR (va dan)) dau su viet.
• Adding a wildcard symbol may retrieve word variants: te sac ky dang xa hoi. ((hieu va) or (hieu qua)) co tuc ((va danh) or (va dan)) dau su viet*.