Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thanh lap » thanh san, phan lap, thanh hai
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
ty hang » ly hang, ty xang, thi hang
van cac » van hac, van cau, van bac
ty nang » ky nang, ty xang, ly nang
lap cua » lai cua, tap cua, lam cua
dac va » day va, dat va, dai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((ty nang) or (ty hang)) xa hoi. hieu van cac ((dac va) OR (duc va)) thanh lap cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty nang) OR (ty hang)) xa hoi. hieu van cac ((dac va) OR (duc va)) thanh lap cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ty nang) or (ty hang)) xa hoi. hieu van cac ((dac va) OR (duc va)) thanh lap cua triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ty nang) or (ty hang)) xa hoi. hieu van cac ((dac va) OR (duc va)) thanh lap cua triet*.