Perhaps you should try some spelling variations:
tao khoi » thao khoa, lao khoa, tao boi
luoc dai » cuoc doi, hoc dai, duc dai
cua tre » cua te, cuu tre, cua triet
hanh di » hanh vi, hanh de, hang di
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
ky sang » ky nang, ky dang, ky tang
tao hoi » tao boi, tay hoi, thao hoc
ve cac » va cac, vien cac
san ky » sang ky, van ky, dan ky
di cua » dai cua, doi cua, de cua
te san » te ban, ke san, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: te san ky sang ((tao khoi) OR (tao hoi)). hieu ve cac ((duc van) or (luoc dai)) hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te san ky sang ((tao khoi) OR (tao hoi)). hieu ve cac ((duc van) OR (luoc dai)) hanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te san ky sang ((tao khoi) OR (tao hoi)). hieu ve cac ((duc van) or (luoc dai)) hanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: te san ky sang ((tao khoi) OR (tao hoi)). hieu ve cac ((duc van) or (luoc dai)) hanh di cua tre*.