Perhaps you should try some spelling variations:
hien bach » vien bach, thien hach, dien sach
hien hanh » dieu hanh
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
va danh » va dinh, va dan, va hanh
co sac » co sach, co cac, cao sach
sac ky » cac ky, sai ky
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: co sac ky lang xa hoi. hieu ((hien bach) OR (hien hanh)) nuoc va danh ((vi cua) OR (di cua)) tu~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sac ky lang xa hoi. hieu ((hien bach) or (hien hanh)) nuoc va danh ((vi cua) OR (di cua)) tu~".
• Adding a wildcard symbol may retrieve word variants: co sac ky lang xa hoi. hieu ((hien bach) or (hien hanh)) nuoc va danh ((vi cua) OR (di cua)) tu*.