Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh loi » thanh hoa, thanh hai, thanh lap
dong ban » dong bang, dong san, dong bac
tac dong » tac dung, tac trong, ha dong
cua tre » cuu tre, cua triet, dua tren
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ve tac » va tac, ve cac, ve tai
nang o » nang co, nang ho, nang ro
cua tu » cua tuc, cua su, cua cu
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 ky nang o hoi. hieu ve tac dong ban thanh loi ((cua tre) or (((cua te) OR (cua tu))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang o hoi. hieu ve tac dong ban thanh loi ((cua tre) OR (((cua te) OR (cua tu)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang o hoi. hieu ve tac dong ban thanh loi ((cua tre) or (((cua te) OR (cua tu))))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang o hoi. hieu ve tac dong ban thanh loi ((cua tre) or (((cua te) OR (cua tu))))*.