You can go back to earlier search results by viewing your search history. Each set of results is a link that will take you back to that search.
To save a search history to run at a later time, first create a free account with Web of Science.
Search histories can be set to re-run automatically as an alert.
To manually run a saved search, select Saved Searches and Alerts from the My Tools drop-down menu. Click on Browse to locate your search, then click on Open. On the list of saved searches, you can delete a search or modify the settings before running it.
