Hi!
rg --search-zip -F "http://www.wikidata.org/prop/direct-normalized" wikidata_latest-truthy.nt.bz2 | pv > wikidata-extids.txt
But I get as a result a little less than 29.5 million lines. Pubmed and DOI, which alone account for about 33 million statements, are not included.
Could you provide specific properties and preferably also some Q-ids for which you expected to find direct-normalized props but didn't?