Perhaps you should try some spelling variations:
hanh lai » hanh lam, hanh tai, thanh lap
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
su tien » su hien, tu tieng, dau tien
duc van » duc va, duc tan, duc manh
cam duc » cam xuc, cao duc, pham duc
hieu ve » hieu va, hieu van
lai roi » lai hoi, loi roi
ty hang » ly hang, ty xang, thi hang
ty mang » ty xang, tin mang, tri mang
ve cam » ve cham, ve cac, va cam
kien » bien, vien, dien

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 ((ty mang) or (ty hang)) lai roi. hieu ve cam duc van hanh lai ((su tien) OR (su kien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty mang) OR (ty hang)) lai roi. hieu ve cam duc van hanh lai ((su tien) OR (su kien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty mang) or (ty hang)) lai roi. hieu ve cam duc van hanh lai ((su tien) OR (su kien))".
• Adding a wildcard symbol may retrieve word variants: su sach ((ty mang) or (ty hang)) lai roi. hieu ve cam duc van hanh lai ((su tien) OR (su kien))*.