Perhaps you should try some spelling variations:
ve triet » va trien, su triet
va triet » va thiet, va trien, cua triet
van hanh » van thanh, ban hanh, van anh
chat soc » cham soc, chat hoc, chat doc
sang ma » tang ma, sang tao, mang may
va chat » van chat, va phat, cao chat
soc van » hoc van, oc van, sac van
hanh di » hanh vi, hanh de, hang di
nang ma » tang ma, nang cao, mang may
san ky » sang ky, van ky, dan ky
tu san » thu san, tu ban, tu can

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 ((nang ma) OR (sang ma)) hoi. lieu va chat soc van hanh di ((va triet) or (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky ((nang ma) OR (sang ma)) hoi. lieu va chat soc van hanh di ((va triet) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu san ky ((nang ma) OR (sang ma)) hoi. lieu va chat soc van hanh di ((va triet) or (ve triet))".
• Adding a wildcard symbol may retrieve word variants: tu san ky ((nang ma) OR (sang ma)) hoi. lieu va chat soc van hanh di ((va triet) or (ve triet))*.