Perhaps you should try some spelling variations:
hieu tieng » viet tieng, dien tieng, tiep tieng
hieu hien » bieu hien, dieu hien, chieu chien
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
hanh dao » lanh dao, thanh dat, thanh dam
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
dao cua » dai cua, day cua, dan cua
san ky » sang ky, dan ky, ban ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((san ky) OR (van ky)) nang x ho. ((hieu tieng) or (hieu hien)) cac tuc van hanh dao cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((san ky) OR (van ky)) nang x ho. ((hieu tieng) OR (hieu hien)) cac tuc van hanh dao cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((san ky) OR (van ky)) nang x ho. ((hieu tieng) or (hieu hien)) cac tuc van hanh dao cua triet".
• Adding a wildcard symbol may retrieve word variants: tu ((san ky) OR (van ky)) nang x ho. ((hieu tieng) or (hieu hien)) cac tuc van hanh dao cua triet*.