I didn't know what else to say.

我不知道还能再说点什么。

《柯林斯英汉双解大词典》

There's nothing else to say.

没有其他想说的。

youdao

I'm not sure how else to say it.

我不知道还能怎样表达。

youdao

The World Health Organization and the World Bank say people with disabilities should be able to use the same services as everyone else.

VOA: special.2011.06.29

reciting the text, emoting over it, enthusing about it, - and then looking around for something else to say-- it was no longer a question of doing that.

或者只是背诵篇子，装模作样地读一读，假装很感兴趣，然后没话找话的评论一番-,现在意义上的精读可不是这样的了。

耶鲁公开课 - 文学理论导论课程节选

Yeah, I don't know really what else to say. Just he's awesome.

我真不知道还能说些什么。总之就是他太棒了。

喜欢的电视节目 - SpeakingMax英语口语达人

"There's nothing else to say, it speaks for itself, it's wrong to do, " Emanuel said.

NPR: Goat's Head Delivered To Wrigley Field

But a better reason is simply the fact that they have nothing else to say.

FORBES: Guilt by Association

Frankly, I was starting to wonder if there was anything else to say short of "it's a horrible mess!"

CNN: Quest: U.S. economy to dominate Davos 2013