The DataAssist search results page has built in functionality that causes any search to be saved so that if the visitor comes back to the page (such as going to the detail page and then update page and then back to the results page) that the search will still be present.
If that isn't the desired behavior, then you can work around it by linking to the results page and add in a "fake" query string value such as results.php?clear=true
This will cause the "search save" feature to think that another search is being performed with no search criteria (assuming that "clear" isn't the name of one of your search fields), which will show all of the records.
HTH