SearchWP was built to automatically maintain its own index without you having to do anything. When you first activate SearchWP the initial index is built, and then SearchWP will apply delta updates to only content that is added/edited/removed in the background.
There are times, however, where you may want (or need) to rebuild the index entirely. This usually comes up when you’ve added or edited a hook that requires the index to be rebuilt so as to apply the changes implemented in the hook.
Rebuilding the SearchWP index is easy, begin by clicking the Advanced tab on the main SearchWP settings screen:
On the Advanced Settings page, click the Reset Index button:
Once you’ve done that you will see a link to start the indexing process. Clicking that link will cause the index to be rebuilt, and SearchWP will continue making delta updates as expected.