If you are experiencing problems finding products containing å, ä or ö it is most likely due to the search being case sensitive. So if a product is for example named "Äpple" you will need to search with an uppercase Ä. This only applies to the letters å, ä, ö.
A workaround for this is to enter the product name with lowercase letters in the Custom fields of the product. For example on Custom 4. Enter "äpple" in the Custom 4 field. This will enable searches for the product in lowercase as well as uppercase.
If you have further inquires regarding what you can and cannot search for, please contact Sitoo Support at firstname.lastname@example.org and we will be happy to assist you.