Here's how you can replace the Search key on your Chromebook with Caps Lock.
1. Go to Settings.
2. Go to Keyboard Settings.
3. Click the Search dropdown menu and choose Caps Lock.
4. Click the OK button to save your change.
Google put the Search button in place of the Caps Lock key. Some like that change but others like me need the Caps Lock key. That's easy to fix in the keyboard settings in Chrome.More at ZDNet
Additional resources for Chromebooks