An example, we have a village such as "Cieszyna 88". How did it happen in many villages in Poland there are no streets. And here is the problem of finding the address. Invented to add a tag addr: place = name of the village. Example Cieszyna 88:
addr:city = Cieszyna, addr:housenumber = 88 , addr:place = Cieszyna, addr: postcode = 38-125
Nominatim can search for these addresses. And I think I can find these addresses in OsmAnd.
http://nominatim.openstreetmap.org/search.php?q=Cieszyna+88&viewbox=-39.47,66.52,80.6,34.37
http://www.openstreetmap.org/#map=19/49.86374/21.61691
I can not explain otherwise. If you want you can ask on the forum for more details.
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