1) - When using Advanced search to search keywords:
2) - Select the first checkboxes if you would like to include variant forms and spellings for search terms. Select the third checkbox to show the variant spellings and variant forms of your keyword on top of the result list.
3) - The variant spellings and variant forms of your keyword can be listed on top of the result list.
4) - Click this link if you would like the result list without variants.