Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
ky dang » ky nang, ky danh
hoa hoi » khoa hoi, hoa hoc, hoa doi
ky lang » ky nang, ky tang, tay lang
van cam » van nam, van lam, van cau
va danh » va dinh, va dan, va hanh
xuc va » duc va, tuc va, luc va
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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 ((ky lang) or (ky dang)) hoa hoi. hieu van cam xuc va danh ((vi cua) or (di cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ky lang) OR (ky dang)) hoa hoi. hieu van cam xuc va danh ((vi cua) OR (di cua)) triet.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ky lang) or (ky dang)) hoa hoi. hieu van cam xuc va danh ((vi cua) or (di cua)) triet*.