You can do this via the query string.  Some of the options are:

grm2catid - pass in the category id's you'd like to see (?grm2catid=2)

attrib - the attribute id you'd like to see (?attrib=5)

grm2auid - search text to include

id - the id of the individual item you'd like to see

Unfortunately you only see the category names in the settings of the module.  But the following queries will retrieve the id's for the categories and attributes in your module:

select itemid, category from grmrepositorycategories

select itemid, valuename from grmrepositoryattributevalues