draw a blank 白费力气，一无所得

例句：

I think she's posing as a human. She's changed her eye color, wearing human clothes. That's why we're drawing a blank.

我想她是扮成了人类。她更改了瞳孔的颜色，穿上了人类的衣服。这就是为什么我们一直没有进展。

Notes: draw a blank正如它的字面意思，在口语中表示“无结果，无收获，扑空”等。例：

She lost her gloves yesterday and looked for it everywhere but she's drawn a blank so far.

她昨天把手套弄丢了，到处找，直到现在也没找到。