Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
nang xa » nang x, mang xa, ang xa
lang xa » lang ha, dang xay, lang van
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
xuc van » duc van, luc van, xuc ban
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
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: tu sach y ((((nang xa) or (lang xa))) or (nang ma)) hoi. hieu ve cam xuc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((((nang xa) OR (lang xa))) OR (nang ma)) hoi. hieu ve cam xuc van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((((nang xa) or (lang xa))) or (nang ma)) hoi. hieu ve cam xuc van hanh vi cua tre*.