Perhaps you should try some spelling variations:
van nang » van quang, van dong, van dung
van hanh » van thanh, ban hanh, van anh
su triet » su tien, ve triet
vu sach » vu bach, su sach, vu khach
hieu ve » hieu va, hieu van
cam luc » cam xuc, cau luc
luc van » luoc van, luu van, duc van
su viet » so viet
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ((van nang) or (van ban)) xa hoi. hieu ve cam luc van hanh vi ((su triet) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ((van nang) OR (van ban)) xa hoi. hieu ve cam luc van hanh vi ((su triet) OR (su viet)).
• Adding a wildcard symbol may retrieve word variants: vu sach ((van nang) or (van ban)) xa hoi. hieu ve cam luc van hanh vi ((su triet) or (su viet))*.