Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
danh dau » lanh dao, hang dau, danh tu
tai thuy » thai thuy, thi thuy, hai thuy
ve triet » va trien, su triet
ty hang » ly hang, ty xang, thi hang
mai hoi » mai khoi, dai hoi, lai hoi
thuy va » thuy van, thuc va, thue va
va danh » va dinh, va dan, va hanh
ly nang » ky nang, ly hang, ly vang
ma hoi » xa hoi, ma hoa, me hoi
va tai » va tac, va tap
dau ve » dap ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ly nang) or (ty hang)) ((ma hoi) or (mai hoi)). lieu va tai thuy va danh dau ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ly nang) OR (ty hang)) ((ma hoi) OR (mai hoi)). lieu va tai thuy va danh dau ve triet.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ly nang) or (ty hang)) ((ma hoi) or (mai hoi)). lieu va tai thuy va danh dau ve triet*.