Perhaps you should try some spelling variations:
ban hanh » ban hang
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
luu ban » luu bang, luu van, luu dan
cua tre » cua te, cuu tre, cua triet
ve cac » va cac, vien cac
nang o » nang co, nang ho, nang ro
vi cua » vai cua, di cua
ve cam » ve cham, va cam, ve cai
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) OR (thu sach)) ky nang o hoi. hieu ((ve cam) or (ve cac)) luu ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang o hoi. hieu ((ve cam) OR (ve cac)) luu ban hanh vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang o hoi. hieu ((ve cam) or (ve cac)) luu ban hanh vi cua tre*".