Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, hoc sach, cuoc cach
ban hanh » ban hang
phan dai » phan dau, phan day, phan loai
tay lang » tai lang, tay tang, tay quang
hieu ve » hieu va, hieu van
dai ban » dai han, tai ban, di ban
ve phan » va phan, ke phan, ve phat
vi su » va su, ki su, oi su
ve su » va 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 xang) or (tay lang)) xa hoi. hieu ve phan dai ban hanh ((vi su) OR (ve su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nuoc sach ((ty xang) OR (tay lang)) xa hoi. hieu ve phan dai ban hanh ((vi su) OR (ve su)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nuoc sach ((ty xang) or (tay lang)) xa hoi. hieu ve phan dai ban hanh ((vi su) OR (ve su)) triet".
• Adding a wildcard symbol may retrieve word variants: nuoc sach ((ty xang) or (tay lang)) xa hoi. hieu ve phan dai ban hanh ((vi su) OR (ve su)) triet*.