go unobserved
pass unobserved

But all of them knew each other thoroughly, and no action went unobserved.

Any march through the desert would not go unobserved, sir.

This made it much more difficult for troop movements to go unobserved.

I have no servant and there is something here which makes it hard for me to go about the city unobserved.

It was dawn by the time the tiger left the city, but he did not go unobserved.

Moneo did not take this to mean that his approach went unobserved.

The Auden anniversary, however, will not go unobserved in this city.

Luckily, no one was in the room at the time and his appearance out of nowhere went unobserved.

The movement went unobserved with all attention centered on Molina.

Some pilots were known to have gone unobserved over the enemy at 200 feet.