Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
tay lang » tai lang, tay tang, tay quang
ban hanh » ban hang
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
hieu ke » hieu kem, chieu ke, hieu ky
ke phan » ve phan, kenh phan, ke thang
phan do » phan bo, phan co, phan mo
y lang » o lang, _ lang, yen lang
vi su » va su, ve su, ki su

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: su sach ((y lang) OR (tay lang)) xa hoi. hieu ke phan do ((van thanh) OR (ban hanh)) vi su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y lang) OR (tay lang)) xa hoi. hieu ke phan do ((van thanh) or (ban hanh)) vi su triet~".
• Adding a wildcard symbol may retrieve word variants: su sach ((y lang) OR (tay lang)) xa hoi. hieu ke phan do ((van thanh) or (ban hanh)) vi su triet*.