Perhaps you should try some spelling variations:
thai thuc » thai thuy, thai tuc, tham thuc
thien van » thi van
cua triet » cua viet, su triet, va triet
hieu van » hieu va, lieu va, hieu ve
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cua tre » cua te, cuu tre, dua tren

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

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