Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, hoc sach, cuoc cach
ban hanh » ban hang
su triet » su viet, su tien, ve triet
tay lang » tai lang, tay tang, tay quang
ve phan » ke phan, ve phat, vi phan
va phan » van phan, va phat, va phap
dai ban » dai han, tai ban, di ban
ty lang » ty xang, ty hang, tu lang
vi su » va su, ve su, ki su

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

• Performing a fuzzy search may retrieve terms with similar spellings: nuoc sach ((ty lang) or (tay lang)) xa hoi. hieu ((ve phan) OR (va phan)) dai ban hanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nuoc sach ((ty lang) OR (tay lang)) xa hoi. hieu ((ve phan) OR (va phan)) dai ban hanh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nuoc sach ((ty lang) or (tay lang)) xa hoi. hieu ((ve phan) OR (va phan)) dai ban hanh vi su triet".
• Adding a wildcard symbol may retrieve word variants: nuoc sach ((ty lang) or (tay lang)) xa hoi. hieu ((ve phan) OR (va phan)) dai ban hanh vi su triet*.