Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dang xay » dang van, van xay
dao cua » dai cua, day cua, dan cua
anh dao » lanh dao, hanh dao, anh dat
duc van » duc va, duc tan, duc manh
luc van » luoc van, luu van, luc va
hieu va » lieu va, hieu qua
lang ha » long ha
va cam » va cham, va cac, va cao
bai ky » ban ky, sai ky, bac ky
tu bai » tu ban, tu bat, te bai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu bai ky ((lang ha) or (dang xay)) hoi. hieu va cam ((luc van) OR (duc van)) anh dao cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu bai ky ((lang ha) OR (dang xay)) hoi. hieu va cam ((luc van) OR (duc van)) anh dao cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu bai ky ((lang ha) or (dang xay)) hoi. hieu va cam ((luc van) OR (duc van)) anh dao cua triet".
• Adding a wildcard symbol may retrieve word variants: tu bai ky ((lang ha) or (dang xay)) hoi. hieu va cam ((luc van) OR (duc van)) anh dao cua triet*.