Perhaps you should try some spelling variations:
ban hanh » ban hang
hanh lai » hanh lam, hanh tai, thanh lap
sach ty » sach y, sach tu, sach thu
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
duc ban » duc tan, duc van, dua ban
su tien » su kien, su hien, tu tieng

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) or (sach thieu)) lang xa hoi. hieu va cac duc ban hanh lai su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thieu)) lang xa hoi. hieu va cac duc ban hanh lai su tien.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach thieu)) lang xa hoi. hieu va cac duc ban hanh lai su tien*.