Perhaps you should try some spelling variations:
sang mai » sang ma, sang tai, lang mai
nam duoc » nam thuoc, da duoc, dat duoc
cua tre » cua te, cuu tre, cua triet
va danh » va dinh, va dan, dia danh
ky sang » ky nang, ky dang, ky tang
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
lai cua » dai cua, hai cua, lai chau
va hanh » van hanh, va thanh, ban hanh
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky

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 mai hoi. hieu ve ((nam duoc) or (cam xuc)) ((va danh) OR (va hanh)) lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky sang mai hoi. hieu ve ((nam duoc) OR (cam xuc)) ((va danh) OR (va hanh)) lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky sang mai hoi. hieu ve ((nam duoc) or (cam xuc)) ((va danh) OR (va hanh)) lai cua tre".
• Adding a wildcard symbol may retrieve word variants: te sac ky sang mai hoi. hieu ve ((nam duoc) or (cam xuc)) ((va danh) OR (va hanh)) lai cua tre*.