Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
dai hai » dai han, dai hoi, dai tai
hieu ve » hieu va, hieu van
cac luc » cau luc, coc luc, cac nuoc
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va

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 ((cau hoi) or (dai hai)). hieu ve cac luc va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky nang ((cau hoi) OR (dai hai)). hieu ve cac luc va hanh tai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sac ky nang ((cau hoi) or (dai hai)). hieu ve cac luc va hanh tai cua tre*.