Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, hoc sach, cuoc cach
ban hang » ngan hang
phan dai » phan dau, phan day, phan loai
ty hang » ly hang, ty xang, thi hang
hieu ve » hieu va, hieu van
dai ban » dai han, tai ban, di ban
ty lang » tay lang, ty xang, tu lang
ve phan » va phan, ke phan, ve phat
vi su » va su, ve su, oi su
ki su » ky 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 (ty hang)) xa hoi. hieu ve phan dai ban hang ((vi su) or (ki su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nuoc sach ((ty lang) OR (ty hang)) xa hoi. hieu ve phan dai ban hang ((vi su) OR (ki su)) triet.
• Adding a wildcard symbol may retrieve word variants: nuoc sach ((ty lang) or (ty hang)) xa hoi. hieu ve phan dai ban hang ((vi su) or (ki su)) triet*.