There was a vacant look in her eyes that worried him.

She had that vacant look some young girls get around men.

When Richard greeted the people, he got back only vacant looks.

A house was nearby, but it had a vacant look.

A vacant look, almost like fear, came on the fellow's face.

There was a kind of vacant look on her face.

He shook his head and stared with a vacant look.

The vacant look on his face makes it clear he doesn't know what to say.

But he had the same vacant look to his eyes.

He saw the vacant look on my face and laughed.