Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach lo » sach dao, sach doi, sach hoi
lo hang » ly hang, le hang, cho hang
qua xay » luat xay, luan xay, xuat xay
xay duc » xa duc, xay dung, xuan duc
va hanh » van hanh, va thanh, va danh
vai cua » hai cua, lai cua, bai cua
va hoi » xa hoi, va hoc
va hoa » van hoa, va hoc, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach lo hang ((va hoi) or (va hoa)). hieu qua xay duc va hanh ((vai cua) OR (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach lo hang ((va hoi) OR (va hoa)). hieu qua xay duc va hanh ((vai cua) OR (dai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach lo hang ((va hoi) or (va hoa)). hieu qua xay duc va hanh ((vai cua) OR (dai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach lo hang ((va hoi) or (va hoa)). hieu qua xay duc va hanh ((vai cua) OR (dai cua)) triet*.