Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, cau treo
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
cham tu » pham tu, cam tu, chai tu
va hanh » van hanh, va thanh, va danh
ca tren » cu tren, la tren, co tren
sac ky » cac ky, sai ky

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sac ky)) nang xa hoi. hieu ve cham tu va hanh vi ((ca tren) OR (cau tren))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) OR (sac ky)) nang xa hoi. hieu ve cham tu va hanh vi ((ca tren) or (cau tren))~".
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) OR (sac ky)) nang xa hoi. hieu ve cham tu va hanh vi ((ca tren) or (cau tren))*.