Perhaps you should try some spelling variations:
van dung » van dong, xay dung, tin dung
cham duc » pham duc, cham soc, pham duy
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
duc van » duc va, duc tan, duc manh
vi su » ve su, ki su, oi su

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

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