Perhaps you should try some spelling variations:
hieu va » lieu va, hieu qua
cac luc » cau luc, coc luc, cac nuoc
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
dinh ca » dinh cac, dinh cua, dinh cao
va dinh » van dinh, va kinh, va tinh
cua tu » cua tuc, cua su, cua te
tu sac » tu sach, tu cac, tu san
luc va » duc va, tuc va, loc va
sac ky » cac ky, sai ky
cua cu » cua chu, cua cau, cua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang xa) OR (nang ma)) hoi. hieu va cac luc va dinh ca ((cua tu) or (cua cu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang xa) OR (nang ma)) hoi. hieu va cac luc va dinh ca ((cua tu) OR (cua cu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((nang xa) OR (nang ma)) hoi. hieu va cac luc va dinh ca ((cua tu) or (cua cu))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang xa) OR (nang ma)) hoi. hieu va cac luc va dinh ca ((cua tu) or (cua cu))*.