Perhaps you should try some spelling variations:
van khanh » van thanh, van hanh, van anh
than cua » nhan cua, thai cua, ban cua
van khan » van khang, van phan, van nhan
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
cac xuc » cam xuc, cac nuoc, chat xuc
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
co hoi » co hoc, co loi
ve cac » va cac, vien cac
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky nang ((co hoi) or (o hai)). hieu ve cac xuc ((van khan) OR (van khanh)) than cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang ((co hoi) OR (o hai)). hieu ve cac xuc ((van khan) OR (van khanh)) than cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang ((co hoi) or (o hai)). hieu ve cac xuc ((van khan) OR (van khanh)) than cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ((co hoi) or (o hai)). hieu ve cac xuc ((van khan) OR (van khanh)) than cua tre*.