Hello, @Henrik Kriiger,
Translation files include only strings that were used in PHP files and can’t be edited from the Theme Options or backend. Search placeholder text of the header builder element is custom text and it can be changed via Theme Options > Header builder > Search, it’s not included to translation files because it’s not hardcoded. If you create multilanguage site using WPML for example then all the strings from the admin module could be added to the translation using WPML settings http://prntscr.com/qxsbgb to translate them to other languages.
1) Go to Theme Options > Header builder > edit search and translate the search placeholder text to your language.
2) After that you need to translate these admin strings to other languages of your site. To do this go to WPML > String translator > scroll down and click translate admin strings > check the strings you need to translate and add them to string translator.
3) Go back to string translator and translate strings to other languages.
Regards 8Themes Team.
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