How to find a cat hiding in someone else's house
If a cat runs into someone else's house and can't get out, and that house is usually empty, you can consider taking the following measures:
1. Contact your local animal protection association or rescue organization for help. They usually have the professional tools and skills to enter homes to capture or guide cats.
2. Look for the cat's hiding places around the house. You can use cat food, cat toys, or other bait to lure it out. Once you find the cat, you can use professional tools such as animal traps or cat cages to bring it back. 
3. If you cannot find the cat, you can consider setting up some cat bait around the house, such as food and water, to lure the cat out on its own.
4. If the above measures fail to resolve the issue, consider consulting with a professional pet behavior specialist or animal behavior expert for advice and guidance.
It's important to be patient and careful when catching or guiding a cat to avoid harming or frightening it. After resolving the cat's issue, consider strengthening cat surveillance and protection measures around the house to prevent similar incidents from recurring.
