Perhaps you should try some spelling variations:
dung dai » duong dai, dung tai, dung dat
su sach » vu sach
xa dung » xay dung, xa dong, va dung
cam tuc » cam tu, nam thuc, dam thuc
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

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 ma hoi. hieu ve ((cam tuc) or (cam xuc)) xa dung dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky nang ma hoi. hieu ve ((cam tuc) OR (cam xuc)) xa dung dai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky nang ma hoi. hieu ve ((cam tuc) or (cam xuc)) xa dung dai cua tre*.