Perhaps you should try some spelling variations:
sach kem » hanh kem
luat tuc » luat thue
tinh di » tinh doi, trinh di, tinh da
tuc may » truc may, tu may, tuc xay
va luat » va thuat, vay luan, cua luat
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, me hoi
sac ky » cac ky, sai ky
di cuu » di cau, di cua, dinh cuu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach kem) or (sac ky)) nang ((ma hoi) OR (ma hoa)). hieu va luat tuc may tinh di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach kem) OR (sac ky)) nang ((ma hoi) OR (ma hoa)). hieu va luat tuc may tinh di cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach kem) or (sac ky)) nang ((ma hoi) OR (ma hoa)). hieu va luat tuc may tinh di cuu tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach kem) or (sac ky)) nang ((ma hoi) OR (ma hoa)). hieu va luat tuc may tinh di cuu tre*.