Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
su triet » su viet, su tien, ve triet
dang van » hoang van, hang va
cham hoc » cham soc, chat hoc, cham hoi
va cham » va chat, va tham
sang ky » sang kyo, dang ky, tang ky
van hoi » van hoa, van hoc, van hoe
hanh de » hanh ve, hanh kem
hoc van » hoc dan, hoc va, hoc vat
san ky » van ky, dan ky, ban ky
thiet » thieu

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) or (sang ky)) dang van hoi. lieu va cham hoc van hanh de ((su triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((san ky) OR (sang ky)) dang van hoi. lieu va cham hoc van hanh de ((su triet) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: tu ((san ky) or (sang ky)) dang van hoi. lieu va cham hoc van hanh de ((su triet) or (va thiet))*.