Perhaps you should try some spelling variations:
cua tre » cua te, cuu tre, cua triet
vai cua » dai cua, hai cua, lai cua
va tinh » may tinh
va dinh » van dinh, va kinh, vu dinh
qua cao » qua cac, qua ca, qua cai
cao tuc » dao tuc, cao duc, cao suc
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
cam ky » cao ky, cac ky
tu cam » tu cham, tu cac, tu nam

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

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