Don't stray from the point.

不要离题乱扯。

《新英汉大辞典》

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

请不要离开本题。

《新英汉大辞典》

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

他的书籍都没有脱离主题。

youdao

During that time, while on tour in Europe and Southeast Asia, he decided to stray from his usual regimen of smooth jazz and focus on the jazz classics he heard growing up.

VOA: standard.2010.04.12

The streets are mostly flat. Rick Fire,Waterz' partner, was wounded several years ago by a stray bullet on the way home from school.

VOA: standard.2010.07.27

London (CNN) -- Herge's famous boy reporter certainly liked to stray from his native Belgium.

CNN: Comic book hero Tintin's archaeological escapades

Many dogs are even trained to track children who stray from home by following their scent.

CNN: Dogs work 'magic' on kids with autism

He spares no one, including congressional Republicans when they stray from their principles.

FORBES: Fact and Comment