Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
cua tre » cua te, cuu tre, cua triet
hai cua » thai cua, dai cua, hoi cua
va hanh » van hanh, va thanh, va danh
hieu ve » hieu va, hieu van
dai hai » dai han, dai hoi, dai tai
dai moi » doi moi, dai hoi
sai ky » sac ky
luc va » duc va, tuc va, loc va
su sai » su tai, su hai, su dai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sai ky nang ((dai moi) or (dai hai)). ((hieu ve) or (hieu qua)) coc luc va hanh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sai ky nang ((dai moi) OR (dai hai)). ((hieu ve) OR (hieu qua)) coc luc va hanh hai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sai ky nang ((dai moi) or (dai hai)). ((hieu ve) or (hieu qua)) coc luc va hanh hai cua tre*.