Perhaps you should try some spelling variations:
luoc van » luoc can, luoc va, luc van
cua tre » cua te, cuu tre, cua triet
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
sac ky » cac ky, sai ky
ve cac » va cac, vien cac
ma hoi » xa hoi, ma hoa, me hoi
vi cua » vai cua, di cua
te sac » te sach, te cac, te 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 sac ky nang ((ma hoi) OR (mai hoi)). hieu ve cac ((duc van) or (luoc van)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang ((ma hoi) OR (mai hoi)). hieu ve cac ((duc van) OR (luoc van)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky nang ((ma hoi) OR (mai hoi)). hieu ve cac ((duc van) or (luoc van)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te sac ky nang ((ma hoi) OR (mai hoi)). hieu ve cac ((duc van) or (luoc van)) hanh vi cua tre*.