Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh vai » thanh hai, thanh van, thanh tai
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
hieu ve » hieu va, hieu van
duc ban » duc tan, duc van, dua ban
ma hoi » mai hoi, xa hoi, me hoi
ve cam » ve cham, ve cac, va cam
vai va » mai va, dai va, hai va
thiet » thieu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ky dang ((ma hoi) or (ma hoa)). hieu ve cam ((cua ban) or (duc ban)) thanh vai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky dang ((ma hoi) OR (ma hoa)). hieu ve cam ((cua ban) OR (duc ban)) thanh vai va thiet.
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky dang ((ma hoi) or (ma hoa)). hieu ve cam ((cua ban) or (duc ban)) thanh vai va thiet*.