Perhaps you should try some spelling variations:
thanh de » hanh de, thanh ve, thanh do
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hieu va » hieu qua
de cua » le cua, te cua, dieu cua
xang x » nang x
cua te » cua tu
tu ma » tu va, te ma
te xa » te va
x hoi » xa hoi, o hoi, x ho

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 xang x hoi. ((hieu va) or (lieu va)) nam ((tu ma) or (te xa)) thanh de cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty xang x hoi. ((hieu va) OR (lieu va)) nam ((tu ma) OR (te xa)) thanh de cua te.
• Adding a wildcard symbol may retrieve word variants: su sach ty xang x hoi. ((hieu va) or (lieu va)) nam ((tu ma) or (te xa)) thanh de cua te*.