I'm going to contradict everything everyone's said now. I went through a similar thing to this when I first got Bess (14 years ago). She was 6 months old when I got her & her previous owners had never had a problem with her. She started to demolish my house. Nothing was safe. She nearly set the house on fire by dragging some paper and cushions close to the front of my coal fire, and I was only out for 20 minutes picking my son up from school! I punished her often but it made no difference. I tried ignoring her, thinking that she would figure out that she had been bad. This went on for some months and then I read somewhere that if a dog is suffering from depression he or she may become destructive. That was a revelation. We then changed tactics completely and started the positive behaviour reinforcement that I always use nowadays. Sadly Bess is no longer with us, she passed away of old age last Summer
What's happening is, she's missing her previous family & home & she doesn't know what to do to make you love her the way they did.
What you need to do is - leave the room just for a couple of minutes, then come back in & if she has been good, praise her & fuss her as if she's done something fantastic. Keep on doing this, I know it sounds stupid to humans, but remember, we're talking about dog brains here
, then increase the time you leave her, each time she's good, praise her to the heavens, lots of squealy happy voices from you "
What a good girly wirly woo you've been" , pick her up, cuddle her, make her feel really special. Keep on doing this, don't ever forget to praise her for good behaviour. When she's naughty, (I know it's hard - I've been there) ignore what she's done, just pick up the shredded cushions/paper, table legs etc, but don't say anything. Just keep up the praise when she's good. I promise you it works (& if it doesn't she can come & live with me & my 2 hooligans)