Perhaps you should try some spelling variations:
sach cam » sach cap, mach cam, sach tham
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
xuc van » duc van, luc van, vuc van
hanh ki » hanh vi, hanh ky, hanh kien
su tien » su hien, tu tieng, dau tien
ma hoi » mai hoi, xa hoi, ma hoa
va cam » va cham, va cao, va cai
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: tu sach cam nang ma hoi. hieu ((va cam) or (va cac)) xuc van hanh ki ((su tien) OR (su kien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach cam nang ma hoi. hieu ((va cam) OR (va cac)) xuc van hanh ki ((su tien) OR (su kien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach cam nang ma hoi. hieu ((va cam) or (va cac)) xuc van hanh ki ((su tien) OR (su kien))".
• Adding a wildcard symbol may retrieve word variants: tu sach cam nang ma hoi. hieu ((va cam) or (va cac)) xuc van hanh ki ((su tien) OR (su kien))*.