Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
sach thu » sach thue, sach thieu, sach tham
va triet » va thiet, va trien, ve triet
hang doi » hang loi, huong doi, hang tai
thu nang » thi nang, thu hang, thu bang
hieu ve » hieu va, hieu van
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
nang xa » nang x, lang xa, nang ma
hang di » hang vi, hang dien, hang dich
so sach » so sanh, bo sach, co sach
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach thu nang xa hoi. hieu ve cac tuc van ((hang doi) OR (hang di)) ((va triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thu nang xa hoi. hieu ve cac tuc van ((hang doi) OR (hang di)) ((va triet) OR (su triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach thu nang xa hoi. hieu ve cac tuc van ((hang doi) OR (hang di)) ((va triet) or (su triet))*".