And the obligatory variation using the  \K operator (see Lookaround Assertions in Extended Patterns in perlre) introduced in Perl version 5.10:

c:\@Work\Perl\monks>perl
use 5.010;  # needs perl version 5.10+ for \K operator

use strict;
use warnings;

my $string = '... data-src-hq="qwe" ... '
           . '... data-src-hq="asd" ... '
           . '... data-src-hq="zxc" ...';

my @matches = $string =~ m{ data-src-hq=" \K [^"]+ (?= ") }xmsg;

print map "'$_' ", @matches;

__END__
'qwe' 'asd' 'zxc'
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