Perhaps you should try some spelling variations:
dang xay » dang van, van xay
nam thuc » nam thuoc, am thuc, nam thu
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
tu sach » thu sach, su sach, te sach
ve nam » he nam, va nam, le nam
vi cua » vai cua, di cua
tu sac » tu cac, tu san, tu bac

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

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