Perhaps you should try some spelling variations:
dang xay » dang van, van xay
hieu va » lieu va, hieu qua
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
va cau » van cau, va cac, va dau
vi cua » vai cua, di cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang cao) OR (dang xay)) hoi. hieu va cau truc va hanh vi cua tre~.
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang cao) or (dang xay)) hoi. hieu va cau truc va hanh vi cua tre*.