Perhaps you should try some spelling variations:
nang cai » nang cao, nang tai, nang cap
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
cai hoi » cau hoi, dai hoi, cai hoa
van cau » van dau, van hau, van chat
cau luc » cau truc, cau phuc
va tinh » may tinh
ban cua » ban quan
cua tre » cua te, cuu tre, cua triet
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky nang cai hoi. hieu van cau luc ((va tinh) or (van hanh)) ban cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky nang cai hoi. hieu van cau luc ((va tinh) OR (van hanh)) ban cua tre.
• Adding a wildcard symbol may retrieve word variants: su sac ky nang cai hoi. hieu van cau luc ((va tinh) or (van hanh)) ban cua tre*.