Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
va thanh » ban thanh, va tinh, le thanh
chu duc » thu duc, chua duoc, cuu duoc
lam cua » nam cua, lam chat
tu sach » thu sach, su sach, te sach
cau duc » cao duc, cau luc, cau truc
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
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 y nang o hoi. hieu van ((cau duc) or (chu duc)) ((va thanh) OR (gia thanh)) lam cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang o hoi. hieu van ((cau duc) OR (chu duc)) ((va thanh) OR (gia thanh)) lam cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang o hoi. hieu van ((cau duc) or (chu duc)) ((va thanh) OR (gia thanh)) lam cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang o hoi. hieu van ((cau duc) or (chu duc)) ((va thanh) OR (gia thanh)) lam cua triet*.