Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
sach ty » sach y, sach tu, sach thu
duc ban » duc tan, duc van, dua ban
tu sach » thu sach, su sach, te sach
van cau » van dau, van hau, van chat
ty nang » ky nang, ty xang, ty hang
cau duc » cao duc, cau luc, chu duc
nang o » nang co, nang ho, nang ro
lam su » lai su, lam so
lam vu » sam vu
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ty nang o hoi. hieu van cau duc ban thanh ((lam su) OR (lam vu)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang o hoi. hieu van cau duc ban thanh ((lam su) OR (lam vu)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang o hoi. hieu van cau duc ban thanh ((lam su) OR (lam vu)) triet*.