Perhaps you should try some spelling variations:
hieu cua » hieu qua, dieu cua, bieu cua
cuu tre » cua tre, cau tren, cau treo
cua cuu » cua chu, cua cau, cua cu
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
cac xuc » cam xuc, cac nuoc, chat xuc
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
sai ky » sac ky
tu sai » tu bai, tu san, tu 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 sai ky ((nang ma) OR (sang ma)) hoi. hieu cua cac xuc ((va danh) or (va hanh)) cua cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sai ky ((nang ma) OR (sang ma)) hoi. hieu cua cac xuc ((va danh) OR (va hanh)) cua cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sai ky ((nang ma) OR (sang ma)) hoi. hieu cua cac xuc ((va danh) or (va hanh)) cua cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sai ky ((nang ma) OR (sang ma)) hoi. hieu cua cac xuc ((va danh) or (va hanh)) cua cuu tre*.