Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
san phan » san pham, sat phan, dan phan
van phan » van phong, van thanh, luan phan
va triet » va thiet, va trien, ve triet
nang xa » nang x, lang xa, nang ma
duc van » duc va, duc tan, duc manh
minh vi » minh voi, dinh vi, minh va
y nang » ky nang, ly nang, v nang
vi va » vi van, vai va, vu va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) y nang xa hoi. hieu ((san phan) OR (van phan)) duc van minh vi va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (doc sach)) y nang xa hoi. hieu ((san phan) OR (van phan)) duc van minh vi va triet~".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (doc sach)) y nang xa hoi. hieu ((san phan) OR (van phan)) duc van minh vi va triet*.