Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
lang van » dang van, tang van, hoang van
cac dac » cac dan, cac dai, cac bac
cac duc » cac du, cao duc, cac nuoc
tuc dan » thuc dan, thuc day, tung dan
lang xa » lang ha, dang xay
hieu va » lieu va, hieu qua
dan ky » van ky
vi su » va su, ve su, ki su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tuc dan ky ((lang xa) or (lang van)) hoi. hieu va ((cac duc) OR (cac dac)) van hanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tuc dan ky ((lang xa) OR (lang van)) hoi. hieu va ((cac duc) OR (cac dac)) van hanh vi su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tuc dan ky ((lang xa) or (lang van)) hoi. hieu va ((cac duc) OR (cac dac)) van hanh vi su triet*".