Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thuc dan » thuc hanh, hoc dan, thuc vat
sach thu » sach thue, sach thieu, sach tham
sach tu » cach tu, sach ty, sach uu
thuc va » thuc vat, thuc day
hieu vi » hieu voi, hieu va, hieu ve
vi cua » vai cua, di cua
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: doc ((sach tu) or (sach thu)) nang x hoi. hieu vi pham ((thuc va) OR (thuc dan)) hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((sach tu) OR (sach thu)) nang x hoi. hieu vi pham ((thuc va) OR (thuc dan)) hanh vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((sach tu) or (sach thu)) nang x hoi. hieu vi pham ((thuc va) OR (thuc dan)) hanh vi cua triet".
• Adding a wildcard symbol may retrieve word variants: doc ((sach tu) or (sach thu)) nang x hoi. hieu vi pham ((thuc va) OR (thuc dan)) hanh vi cua triet*.