Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
va thanh » gia thanh, va tinh, le thanh
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
dau mac » dai mac, dau mat, dau may
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
tai ky » thai ky, trai ky, sai ky
va dau » va dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu tai ky ((nang xa) or (lang xa)) hoi. hieu va dau mac ((va thanh) OR (ban thanh)) doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu tai ky ((nang xa) OR (lang xa)) hoi. hieu va dau mac ((va thanh) OR (ban thanh)) doi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu tai ky ((nang xa) or (lang xa)) hoi. hieu va dau mac ((va thanh) OR (ban thanh)) doi cua tre*".