Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
ban hanh » ban hang
cuc nang » chuc nang, cuu nang, cua nang
va tham » van tham, va thanh, va thuat
hanh ki » hanh vi, hanh ky, hanh kien
xuc ban » duc ban, cuc ban, quoc ban
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
vu nang » vuc nang, va nang, vu dang
va cham » va chat
ki su » ky su

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 ((vu nang) or (cuc nang)) mai hoi. hieu ((va cham) OR (va tham)) xuc ban hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((vu nang) OR (cuc nang)) mai hoi. hieu ((va cham) OR (va tham)) xuc ban hanh ki su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((vu nang) or (cuc nang)) mai hoi. hieu ((va cham) OR (va tham)) xuc ban hanh ki su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((vu nang) or (cuc nang)) mai hoi. hieu ((va cham) OR (va tham)) xuc ban hanh ki su triet*.