Perhaps you should try some spelling variations:
cua triet » su triet, va triet
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
thuc va » thuc vat, thuc dan, thuc day
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 dang xa hoi. hieu van nam thuc va thanh vi ((cua tre) or (((cua triet) or (cua viet))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky dang xa hoi. hieu van nam thuc va thanh vi ((cua tre) OR (((cua triet) OR (cua viet)))).
• Adding a wildcard symbol may retrieve word variants: su sach ky dang xa hoi. hieu van nam thuc va thanh vi ((cua tre) or (((cua triet) or (cua viet))))*.