Perhaps you should try some spelling variations:
hieu nghe » lieu nghe, hiem ngheo, nhiem nghe
su triet » su viet, su tien, ve triet
nghe nam » nghe lam, nghiep nam, nghe nano
nam thuc » nam thuoc, am thuc, nam thu
vat hanh » vat thanh, van hanh, va hanh
hanh ve » hanh vi, hanh va, hanh kem
ky lang » ky nang, ky dang, tay lang
ky tang » ky nang, ky dang, kho tang
hoa hoi » khoa hoi, hoa hoc, hoa doi
tu sac » tu sach, tu cac, tu san
kien » bien, vien, tien

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ((ky lang) OR (ky tang)) hoa hoi. hieu nghe nam thuc vat hanh ve ((su triet) or (su kien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ((ky lang) OR (ky tang)) hoa hoi. hieu nghe nam thuc vat hanh ve ((su triet) OR (su kien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ((ky lang) OR (ky tang)) hoa hoi. hieu nghe nam thuc vat hanh ve ((su triet) or (su kien))".
• Adding a wildcard symbol may retrieve word variants: tu sac ((ky lang) OR (ky tang)) hoa hoi. hieu nghe nam thuc vat hanh ve ((su triet) or (su kien))*.