Option 1: Quick search
If you would like to use the quick search, you first have to enable the respective fields manually.
Only fields for which this is enabled will be taken into account for your overall search.
Navigate to "Settings" and "Field Definition (Objects)"
Click on the pencil-icon on the fields you'd like to consider in the quick search
Activate the "Part of Quick Search"- button and click "Save"
Now you can use the quick search in the object list for the activated fields.
Enter your search term in the search bar, for example "Laptop" and you will see all fields that are searched through for the criteria:
Tip: In Settings - Field definition (objects) you see a list of all fields where the quick search has been activated.
Here you can check again whether you have activated the "Part of Quick search" field for your desired fields:
Option 2: Filter in individual fields
Here you have the possibility to filter the fields more specifically.
You can find more about filters here.