Hi Felix,
I just tried it and I’m able to search it, perhaps it’s due to single quote. Please try this one
Below you'll find a list of all posts that have been categorized as
The ’
is different from '
, and there should be space character after as
. Here is a sample code responsible for that
__( "Below you'll find a list of all posts that have been categorized as ", '__x__' ) . '<strong>“' .
And this strings from POT file which makes it translatable and searchable
msgid "Below you'll find a list of all posts that have been tagged as "
msgstr ""
Thanks!