Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
hanh lai » hanh lam, hanh tai, thanh lap
su triet » su viet, su tien, ve triet
doc sac » doc sach, dac sac, hoc sach
hieu vi » hieu voi, hieu va, hieu ve
thuc va » thuc vat, thuc day
sac ky » cac ky, sai ky
ma hoi » mai hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sac ky nang ((ma hoi) OR (xa hoi)). hieu vi pham ((thuc va) or (thuc dan)) hanh lai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sac ky nang ((ma hoi) OR (xa hoi)). hieu vi pham ((thuc va) OR (thuc dan)) hanh lai su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sac ky nang ((ma hoi) OR (xa hoi)). hieu vi pham ((thuc va) or (thuc dan)) hanh lai su triet".
• Adding a wildcard symbol may retrieve word variants: doc sac ky nang ((ma hoi) OR (xa hoi)). hieu vi pham ((thuc va) or (thuc dan)) hanh lai su triet*.