GeoPandas sjoin returning fewer records than expected

I used GeoPandas sjoin() to merge two Geodataframes. The first one contains 15kk records of buildings and the second one contains all parts of ortofotomap of my country. I have got layer which contains 11.2kk records but I should get the same like the first layer. I was thinking about that and the problem could be when some building stands on 2 parts of map.

What if building stands on 2 parts of map?

Will the code return 2 records, 1, the newest or nothing?

I would like to get 4 records if buildings stands on 4 parts of map because it is possible. For example building can stand in a corner of every from 4 parts of map.

Maybe I should add some argument?

Code:

import geopandas as gpd
    

bud = gpd.read_file('/home/gis/budynkipolska/output.shp')
kaf = gpd.read_file('/home/gis/completed_kafs.shp')

kaf_bud_join = gpd.sjoin(bud, kaf)