Perhaps you should try some spelling variations:
van khanh » van thanh, van hanh, van anh
khanh ve » hanh ve, thanh ve, khanh v
cau theo » cau thi
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach kem
cam tuc » cam xuc, cam tu, nam thuc
tuc van » thuc van, truc van, tuc va
va cam » va cham, va cac, va cao
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sach ty)) nang x hoi. hieu va cam tuc van khanh ve ((cau theo) OR (cau tao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) nang x hoi. hieu va cam tuc van khanh ve ((cau theo) OR (cau tao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach ty)) nang x hoi. hieu va cam tuc van khanh ve ((cau theo) OR (cau tao))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach ty)) nang x hoi. hieu va cam tuc van khanh ve ((cau theo) OR (cau tao))*.