On rocky reliefs (screes, moraines, etc.), the snow generally doesn’t cover all the rocks. While progressing in these environments, the trekker must always have in mind that an air pocket, sometimes deep, can be covered by a more or less solid “snow bridge”. If the weather has remained very cold for several days, you can assume that the bridge will hold.
In any case, it’s better to avoid suspected snow bridges. If there’s no alternative, after checking with your pole, cross it slowly one by one, walking carefully!
The Mountain Guides are trained in snow conditions/avalanches and know how to detect the most common risks. During each of their treks, they will give you their analyses and their thoughts to justify their decision to change the route or goal. In any event you will learn to be cautious.
For more information on snow and avalanches - www.anena.org