Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
duc van » duc va, duc tan, duc manh
cau duc » cao duc, cau luc, chu duc
van cau » van dau, van hau, van chat
te sach » toc sach
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may
nang xa » nang x, lang xa, mang xa
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: te sach ky ((nang xa) or (((nang ma) OR (tang ma)))) hoi. hieu van cau duc van hanh vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang xa) OR (((nang ma) OR (tang ma)))) hoi. hieu van cau duc van hanh vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang xa) or (((nang ma) OR (tang ma)))) hoi. hieu van cau duc van hanh vi va triet".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang xa) or (((nang ma) OR (tang ma)))) hoi. hieu van cau duc van hanh vi va triet*.