Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
sang tao » hang tai
luoc can » luc canh, hoc can, luoc dai
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va
tao hoi » tao khoi, tao boi, tay hoi
ky sang » ky nang, ky dang, ky tang
sai ky » sac ky
vi cua » vai cua, di cua
te sai » te tai, te bai, te lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sai ky sang tao hoi. ((hieu ve) or (hieu van)) cac ((duc van) or (luoc can)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sai ky sang tao hoi. ((hieu ve) OR (hieu van)) cac ((duc van) OR (luoc can)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: te sai ky sang tao hoi. ((hieu ve) or (hieu van)) cac ((duc van) or (luoc can)) hanh vi cua tre*.