Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
duc ban » duc van, duc man, duc manh
dua ban » dia ban, cua ban, qua ban
y nang » ky nang, ly nang, v nang

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 y nang xa hoi. hieu van cam ((((duc ban) OR (duc tan))) or (dua ban)) thanh dai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu van cam ((((duc ban) OR (duc tan))) OR (dua ban)) thanh dai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. hieu van cam ((((duc ban) OR (duc tan))) or (dua ban)) thanh dai cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu van cam ((((duc ban) OR (duc tan))) or (dua ban)) thanh dai cua triet*.