Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
thu sach » thuat sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
cac tuc » cac toc, cac tac, cac nuoc
tu sach » su sach, te sach, tu cach
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
cac tu » cac thu, cach tu, cac du
vi va » vi van, vai va, vu va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thu sach)) ky dang xa hoi. hieu van ((cac tuc) or (cac tu)) van hanh vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky dang xa hoi. hieu van ((cac tuc) OR (cac tu)) van hanh vi va triet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky dang xa hoi. hieu van ((cac tuc) or (cac tu)) van hanh vi va triet*.