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 viet, su tien, ve triet
tu bach » tu cach, tu bac, tu hach
hieu ve » hieu va, hieu van
cam luc » cam xuc, cau luc
luc van » luoc van, luu van, duc van
hanh ki » hanh vi, hanh ky, hanh kien
ve cam » ve cham, ve cac, va cam
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu bach) OR (vu bach)) ((van nang) or (van ban)) xa hoi. hieu ve cam luc van hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu bach) OR (vu bach)) ((van nang) OR (van ban)) xa hoi. hieu ve cam luc van hanh ki su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu bach) OR (vu bach)) ((van nang) or (van ban)) xa hoi. hieu ve cam luc van hanh ki su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu bach) OR (vu bach)) ((van nang) or (van ban)) xa hoi. hieu ve cam luc van hanh ki su triet*.