Perhaps you should try some spelling variations:
dieu cua » dieu tra
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van ban
cua tre » cua te, cuu tre, cua triet
van anh » van thanh, tuan anh, van minh
van dau » van dao, phan dau
dau luc » cau luc, dau luan, dau nuoc
sac ky » cac ky, sai ky
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: te ((sac ky) or (sach thu)) nang x hoi. hieu van dau luc ((van hanh) OR (van anh)) dieu cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sac ky) OR (sach thu)) nang x hoi. hieu van dau luc ((van hanh) OR (van anh)) dieu cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sac ky) or (sach thu)) nang x hoi. hieu van dau luc ((van hanh) OR (van anh)) dieu cua tre*".