Sorry for not being exact enough.
In the DB-field "products_description" I have created a field with additional keywords. This keywords do not show up in the catalog, they are only for customer searches.
The reason is, that a lot of our products (Sporting Goods) have names that are kown with various names or can be spellt in different ways (i.e: The products name is Inlineskate - the customer searches for Rollerskate, Inliners, Rollerblade etc.) and we keep the wrong spellings in this additional field and senable searching in it.
A lot of the additional keywords we already know, but we also log the searches and want to add this words also via EP