Perhaps you should try some spelling variations:
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va hanh » van hanh, va thanh, va danh
lai cua » hai cua, lai chau, thai cua

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 tu nang xa hoi. hieu ve pham duc ((va hanh) or (ban hanh)) ((lai cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu nang xa hoi. hieu ve pham duc ((va hanh) OR (ban hanh)) ((lai cua) OR (dai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: tu sach tu nang xa hoi. hieu ve pham duc ((va hanh) or (ban hanh)) ((lai cua) or (dai cua)) tre*.