2015.1 introduced 'Filter Searches'. You can modify those and add additional filters or turn them off completely.
Here are the steps to access Filter Searches against 2015.1:
1. Log in under the Admin role
2. Click on Configure Application
3. On the left hand side under Settings, expand Search Tools
4. Click on Filter Searches
5. Click Edit next to the business object you want to modify or turn off
6. You can turn off the filter by toggling the on/off switch or modify filters as you need them