Perhaps you should try some spelling variations:
hien cau » khien cau, thien cau, hien cac
kien cau » khien cau, thien cau, ket cau
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
sach ky » sach y, sach ty, sach kem
cam tuc » cam xuc, cam tu, nam thuc
va kinh » va tinh, qua kinh
tuc va » thuc va, truc va, tuc xa
sac ky » cac ky, sai ky
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach ky) OR (sac ky)) nang xa hoi. hieu va cam tuc va kinh ((kien cau) or (hien cau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ky) OR (sac ky)) nang xa hoi. hieu va cam tuc va kinh ((kien cau) OR (hien cau)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ky) OR (sac ky)) nang xa hoi. hieu va cam tuc va kinh ((kien cau) or (hien cau)) tren".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ky) OR (sac ky)) nang xa hoi. hieu va cam tuc va kinh ((kien cau) or (hien cau)) tren*.