Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
sach ky » sac ky, sach y, sach kem
sach ty » sach y, sach tu, sach thu
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai
va co » vo co

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach ky) or (sach ty)) nang o hoi. lieu va co tu ((van hanh) OR (ban hanh)) tri cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ky) OR (sach ty)) nang o hoi. lieu va co tu ((van hanh) OR (ban hanh)) tri cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ky) or (sach ty)) nang o hoi. lieu va co tu ((van hanh) OR (ban hanh)) tri cua triet".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ky) or (sach ty)) nang o hoi. lieu va co tu ((van hanh) OR (ban hanh)) tri cua triet*.