Library Search Fields
Admin with the required permission can configure these fields.
You can enter a phrase or text in the search box and press the Enter key to get the relevant responses from the Response Library. You can configure the desired key fields on Global Library Search such as Confidence Score, Last Review Date, Last Used Date, Valid From, Valid To, Last Used, No. of Times Used, Name, Active, Available, Business Units, External ID, and so on from the Library Search Fields.

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To configure the Library Search fields
Go to Setup and click the Object Manager tab.
Search and select Response from the Quick Find search bar.
Click the Field Sets on the left sidebar.
You can see various field labels display under the field sets.Click the Library Search Fields on the Field Label column.
Drag and drop any of the desired fields from the palette into the list.
Click the Save button.
The changes made will be reflected in the Global Library Search fields.
Below field is fixed and can not be removed or modified from the Library Search page:
Confidence Score
Below fields are default in field set, but can be removed or reordered:
Owner Name
Valid From
Valid To
Source
However, you can add additional custom fields to the Library Search key fields by configuring them.

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If any of the field values are empty in the Response page, those fields will not display on the Global Library Search page.