Perhaps you should try some spelling variations:
cam truc » cau truc, nam truc, lam truoc
dang xay » dang van, van xay
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
hieu va » hieu qua
nang ma » tang ma, sang ma, nang cao
sac ky » cac ky, sai ky
vi cua » vai cua, di cua
tu sac » tu sach, tu cac, tu san

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 ma) OR (dang xay)) hoi. ((hieu va) OR (lieu va)) cam truc va hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((nang ma) or (dang xay)) hoi. ((hieu va) OR (lieu va)) cam truc va hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang ma) or (dang xay)) hoi. ((hieu va) OR (lieu va)) cam truc va hanh vi cua tre*.