Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, cau treo
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
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

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 ky ((nang xa) OR (nang x)) hoi. hieu ve cham tu va hanh vi ((ca tren) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang xa) OR (nang x)) 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 ((nang xa) OR (nang x)) hoi. hieu ve cham tu va hanh vi ((ca tren) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang xa) OR (nang x)) hoi. hieu ve cham tu va hanh vi ((ca tren) or (cau tren))*.