Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
su triet » su viet, su tien, ve triet
thanh va » thanh van, hanh va, thanh ha
va thanh » gia thanh, ban thanh, va tinh
cac truc » cau truc, cac tru, cac trung
vien cac » vien bach, vien dai, vien da
truc va » thuc va, thuc vat, trung va
so sach » bo sach, co sach, hoc sach
so sanh » do sanh
lang o » lang _, tang o, lang son
xang o » tang o, dang o

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) or (so sanh)) ty ((xang o) OR (lang o)) hai. hieu vien cac truc va thanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) ty ((xang o) OR (lang o)) hai. hieu vien cac truc va thanh va su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (so sanh)) ty ((xang o) OR (lang o)) hai. hieu vien cac truc va thanh va su triet".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (so sanh)) ty ((xang o) OR (lang o)) hai. hieu vien cac truc va thanh va su triet*.