Perhaps you should try some spelling variations:
dam thuc » am thuc, dan thuc, nam thuc
dung doi » huong doi, dung tai, dung co
su sach » vu sach
so sach » so sanh, bo sach, co sach
hieu ve » hieu va, hieu van
doi cua » dai cua, hoi cua, dong cua
cua tre » cua te, cuu tre, cua triet
cam tu » cam thu, nam tu, dam tu
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) or (so sach)) ky nang x hoi. hieu ve ((dam thuc) or (cam tu)) xay dung doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky nang x hoi. hieu ve ((dam thuc) OR (cam tu)) xay dung doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky nang x hoi. hieu ve ((dam thuc) or (cam tu)) xay dung doi cua tre*.