Perhaps you should try some spelling variations:
lang van » dang van, tang van, hoang van
nam thuc » nam thuoc, nam thu, nam tu
day hanh » day nhanh, day thanh, dao hanh
bach ky » bac ky
lang xa » lang ha, dang xay
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu bach ky ((lang xa) or (lang van)) hoi. hieu va ((nam thuc) OR (am thuc)) day hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu bach ky ((lang xa) OR (lang van)) hoi. hieu va ((nam thuc) OR (am thuc)) day hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu bach ky ((lang xa) or (lang van)) hoi. hieu va ((nam thuc) OR (am thuc)) day hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: vu bach ky ((lang xa) or (lang van)) hoi. hieu va ((nam thuc) OR (am thuc)) day hanh vi cua tre*.