Perhaps you should try some spelling variations:
sang mai » sang ma, sang tai, lang mai
thuc dan » thuc hanh, hoc dan
cua viet » ca viet, hoa viet, cua vat
ky sang » ky nang, ky dang, ky tang
mai hoi » mai khoi, dai hoi, lai hoi
hieu ly » hieu ky, lieu ly, dieu ly
hang di » hang doi, hang vi, hang dien
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky sang mai hoi. hieu ly nam ((thuc vat) or (thuc dan)) hang di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky sang mai hoi. hieu ly nam ((thuc vat) OR (thuc dan)) hang di cua viet.
• Adding a wildcard symbol may retrieve word variants: su sac ky sang mai hoi. hieu ly nam ((thuc vat) or (thuc dan)) hang di cua viet*.