Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh hai » thanh hai, nhanh hai, hang hai
thu hang » thi hang, thuc hanh, thu huong
nam truc » nam truoc, nam thuc, nam trung
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
so sach » bo sach, co sach, hoc sach
hieu ve » hieu va, hieu van
hang xa » hoang xa, hang va, hang ca
so sanh » do sanh
hai su » hai vu, lai su, hai so

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)) thu hang xa hoi. ((hieu ve) or (hieu qua)) nam truc va hanh hai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) thu hang xa hoi. ((hieu ve) OR (hieu qua)) nam truc va hanh hai su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (so sanh)) thu hang xa hoi. ((hieu ve) or (hieu qua)) nam truc va hanh hai su triet".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (so sanh)) thu hang xa hoi. ((hieu ve) or (hieu qua)) nam truc va hanh hai su triet*.