If the Allow users to search in all columns option is selected in the Web Part settings, a field called Search in all columns for will be displayed in List Search Simple . Enter one or more search terms in this field to search text in all columns of the SharePoint list or library. If configured, this search will also include the content of list item attachments or document library files.
IMPORTANT: This search leverages the SharePoint Search Service and requires that SharePoint Search be enabled and configured. For an item to be found using the Search in all columns for field in List Search Simple , you must also be able to find it in SharePoint Search.
Entering search terms in the Search in all columns for field overrides any search terms entered in other search criteria fields. The Search Criteria Join Operator setting does not apply to this field. For help combining multiple search terms, read Search String Tips and Tricks.