Perhaps you should try some spelling variations:
hieu quan » lieu quan, thien quan, lien quan
cua triet » cua viet, su triet, va triet
hang cau » hang dau, hang ca, nhung cau
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
sach ly » sach y, sach lo, sach ty
ly hang » ly quang
nam xuc » cam xuc, nam xua, nam thuc
va hanh » va thanh, va danh, ban hanh
vi cua » vai cua, di cua

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 ly hang cau hoi. ((hieu quan) or (hieu qua)) nam xuc ((va hanh) OR (van hanh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly hang cau hoi. ((hieu quan) OR (hieu qua)) nam xuc ((va hanh) OR (van hanh)) vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ly hang cau hoi. ((hieu quan) or (hieu qua)) nam xuc ((va hanh) OR (van hanh)) vi cua triet".
• Adding a wildcard symbol may retrieve word variants: su sach ly hang cau hoi. ((hieu quan) or (hieu qua)) nam xuc ((va hanh) OR (van hanh)) vi cua triet*.