Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
mai khoi » mai khoa, tai khoa, cac khoi
dau tren » dau tien, dat tren, dau tieng
mai hoi » dai hoi, lai hoi, mai doi
ky sang » ky nang, ky dang, ky tang
sach ky » sac ky, sach y, sach ty
ve cham » va cham, ve chat, vu cham
va danh » va dinh, va hanh, dia danh
vai dau » va dau, van dau, xvii dau
hieu ve » hieu va, hieu van
va dan » ca dan, va dao, va dau

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 ky sang ((mai hoi) or (mai khoi)). hieu ve cham soc ((va danh) OR (va dan)) vai dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky sang ((mai hoi) OR (mai khoi)). hieu ve cham soc ((va danh) OR (va dan)) vai dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky sang ((mai hoi) or (mai khoi)). hieu ve cham soc ((va danh) OR (va dan)) vai dau tren".
• Adding a wildcard symbol may retrieve word variants: thu sach ky sang ((mai hoi) or (mai khoi)). hieu ve cham soc ((va danh) OR (va dan)) vai dau tren*.