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