Perhaps you should try some spelling variations:
hanh diem » hanh dieu, thanh liem, chanh niem
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ca tren » cau tren, la tren, co tren
va hanh » van hanh, va thanh, va danh
cach tu » cach thuc
va cach » va cac
hieu va » lieu va, hieu qua
nang xa » lang xa, nang ma, mang xa
cu tren » tu tren, dua 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 ty ((nang xa) or (nang x)) hoi. hieu va cach tu va hanh diem ((ca tren) or (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((nang xa) OR (nang x)) hoi. hieu va cach tu va hanh diem ((ca tren) OR (cu tren)).
• Adding a wildcard symbol may retrieve word variants: te sach ty ((nang xa) or (nang x)) hoi. hieu va cach tu va hanh diem ((ca tren) or (cu tren))*.