Don't stray from the point.

不要离题乱扯。

Please keep [stick] to the point.; Please don't stray from the subject.

请不要离开本题。

But I do not stray from your precepts.

我却没有偏离你的训词。

Be careful not to stray from the right path of duty.

注意不要偏离应尽职责的正道。

His books don't stray from those themes in the slightest.

他的书籍都没有脱离主题。