It looks like there is a mess somewhere in OSM base, not sure.

Some streets are available using
Country (England) > City > Street
Some only:
Country (England) > Borough > City > Street (Still looking in London which has 32 boroughs).
But again some boroughs exist in offline base some not.
Searching offline for these streets in Lambeth borough (part of London) makes no results:
Acre Lane
Strathleve Rd
Brixton Hill (Two Brixton... apprear but there is more Brixton names in London in Brixton (district)
All above are in London, Lambeth Borough
or most in London.
Summary, if you don't know all 32 boroughs of London, or don't know the borough of searched street it might be difficult.
Also in England db there is London and City of London, probably for that I need a map

Maybe I'm doing something wrong, don't know, in other countries offline search works easily.
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Right, when changed Norway.map (OAM) to norway.osm.map works perfect with norway.osm.db. (db appears), thanks.