Perhaps you should try some spelling variations:
coc tuc » coc luc, hoc thuc, doc thuc
xa tinh » va tinh, ha tinh, ca tinh
hieu va » lieu va, hieu qua
hieu ve » hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
vu sac » vu sach, vu san, va sac
va va » va vua, va vai, va vat

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sac ky lang xa hoi. ((hieu ve) or (hieu va)) coc tuc xa tinh ((va va) OR (va van)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sac ky lang xa hoi. ((hieu ve) OR (hieu va)) coc tuc xa tinh ((va va) OR (va van)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sac ky lang xa hoi. ((hieu ve) or (hieu va)) coc tuc xa tinh ((va va) OR (va van)) triet".
• Adding a wildcard symbol may retrieve word variants: vu sac ky lang xa hoi. ((hieu ve) or (hieu va)) coc tuc xa tinh ((va va) OR (va van)) triet*.