Perhaps you should try some spelling variations:
thien van » thi van
cua triet » cua viet, su triet, va triet
hieu van » hieu va, lieu va, hieu ve
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang o » nang co, nang ho, nang ro
bo van » vo van, so van, do van
vi cua » vai cua, di cua
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty nang o hai. ((hieu van) or (thien van)) bac bo van hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang o hai. ((hieu van) OR (thien van)) bac bo van hanh vi cua triet.
• Adding a wildcard symbol may retrieve word variants: te sach ty nang o hai. ((hieu van) or (thien van)) bac bo van hanh vi cua triet*.