Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
xuc van » duc van, luc van, vuc van
ve cham » va cham, ve chat, vu cham
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
mang xa » lang xa, mang may, dang xay
vi cua » vai cua, di cua
ve cam » ve cac, va cam, ve cai

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 ((mang xa) or (nang ma)) hoi. hieu ((ve cam) or (ve cham)) xuc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((mang xa) OR (nang ma)) hoi. hieu ((ve cam) OR (ve cham)) xuc van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((mang xa) or (nang ma)) hoi. hieu ((ve cam) or (ve cham)) xuc van hanh vi cua tre*.