Perhaps you should try some spelling variations:
thanh lam » thanh lap, hanh lam, thanh nam
ban thanh » ban hanh, ban hang
ve triet » va trien
hieu van » hieu va, thien van, lieu va
su triet » su viet, su tien
duc ban » duc tan, duc van, dua ban
cau duc » cao duc, cau luc, chu duc
tu sach » thu sach, su sach, te sach
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
van cau » van dau, van hau, van chat
ro hoi » co hoi, o hoi, mo hoi

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) OR (ty hang)) ro hoi. hieu van cau duc ban thanh lam ((su triet) or (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty hang)) ro hoi. hieu van cau duc ban thanh lam ((su triet) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) OR (ty hang)) ro hoi. hieu van cau duc ban thanh lam ((su triet) or (ve triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) OR (ty hang)) ro hoi. hieu van cau duc ban thanh lam ((su triet) or (ve triet))*.