Perhaps you should try some spelling variations:
hien bach » vien bach, thien hach, dien sach
hien hanh » dieu hanh
co sach » bo sach, cuon sach, hoc sach
ky lang » ky nang, ky dang, tay lang
ky tang » ky nang, ky dang, kho tang
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
vi cua » vai cua, di cua
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ((ky lang) OR (ky tang)) xa hoi. hieu ((hien bach) or (hien hanh)) nuoc va danh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ((ky lang) OR (ky tang)) xa hoi. hieu ((hien bach) OR (hien hanh)) nuoc va danh vi cua tu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach ((ky lang) OR (ky tang)) xa hoi. hieu ((hien bach) or (hien hanh)) nuoc va danh vi cua tu*".