Perhaps you should try some spelling variations:
thien van » thi van
nam thuc » nam thuoc, am thuc, nam thu
cau tren » cu tren, dau tren, ca tren
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau treo
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
x hoi » xa hoi, o hoi, x ho

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