Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
mai khoi » mai khoa, tai khoa, cac khoi
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
su triet » su viet, su tien, ve triet
mai hoi » dai hoi, lai hoi, mai doi
sach vu » sach va, sach tu, sach uu
vu nang » vuc nang, va nang, vu dang
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
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: thu sach vu nang ((mai hoi) or (mai khoi)). hieu va cam xuc ((van hanh) OR (ban hanh)) ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach vu nang ((mai hoi) OR (mai khoi)). hieu va cam xuc ((van hanh) OR (ban hanh)) ki su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach vu nang ((mai hoi) or (mai khoi)). hieu va cam xuc ((van hanh) OR (ban hanh)) ki su triet".
• Adding a wildcard symbol may retrieve word variants: thu sach vu nang ((mai hoi) or (mai khoi)). hieu va cam xuc ((van hanh) OR (ban hanh)) ki su triet*.