Hi Britte,
The plugin supports filtering by custom field values as well as taxonomy term filtering.
As long as the custom field values are not complex (like arrays, objects, references), but text, numeric, date – then it should be able to handle them.
To point you to the right direction, I suggest checking the following chapters in the codumentation (includes videos as well):
– Front-end search settings
– Custom field filters how-to
This should hopefully help you out.