My dogs keep getting into things


My dogs are 4 and 2. They've always been really good if we leave them inside while we are gone but lately they have been getting into things way out of their usual reach and some things just get moved from somewhere like a kitchen counter top to the living room. We did have a bag of roca candies on a bookshelf (about 5 feet from the ground) that they got into and ate all of them.

Does anyone have an idea of why their behavior is changing like this? They have toys and our schedules haven't changed recently.

Any insight and/or suggestions would be appreciated.

It's too cold to leave them outside at certain times and I don't want to have to lock them in a crate for hours at a time if we can help it.