in reply to Search in the .tgz file without unpack and untar

Try: 
zcat foo.tgz | tar -xvf - some/wanted/file/path

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IIRC, you could try the above with wildcards as well, e.g. 
zcat foo.tgz | tar -xvf - some/wanted/file/path/date*

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The above should facilitate the extraction of all files having date as a prefix

A user level that continues to overstate my experience :-))

In Section Seekers of Perl Wisdom