Perhaps you should try some spelling variations:
dang xay » dang van, van xay
thuc van » thuc vat, thuc dan, thuc va
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
duc van » duc va, duc tan, duc manh
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: tu sach ty ((nang xa) or (dang xay)) hoi. hieu va cac ((thuc van) or (duc van)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (dang xay)) hoi. hieu va cac ((thuc van) OR (duc van)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang xa) or (dang xay)) hoi. hieu va cac ((thuc van) or (duc van)) hanh vi cua tre*.