Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
hieu van » hieu va, thien van, hieu ve
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
vu van » tu van
vu va » tu va, su va

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 nang x ho. ((hieu van) OR (lieu va)) nam thuc van hanh ((vu va) or (vu van)) trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky nang x ho. ((hieu van) OR (lieu va)) nam thuc van hanh ((vu va) OR (vu van)) trien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky nang x ho. ((hieu van) OR (lieu va)) nam thuc van hanh ((vu va) or (vu van)) trien".
• Adding a wildcard symbol may retrieve word variants: su sac ky nang x ho. ((hieu van) OR (lieu va)) nam thuc van hanh ((vu va) or (vu van)) trien*.