Perhaps you should try some spelling variations:
hieu tieng » viet tieng, dien tieng, tiep tieng
hieu hien » bieu hien, dieu hien, chieu chien
van thanh » ban thanh, van tuan
thanh dam » thanh dat, thanh nam, thanh tam
cua triet » cua viet, su triet, va triet
thu san » thuy san, thu ban, phu san
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
dam cua » dai cua, day cua, nam cua
tu san » tu ban, tu can, vu san

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