similar to Bug 39468 we have Korean source code comments in the hwp filter e.g. http://cgit.freedesktop.org/libreoffice/core/tree/hwpfilter/source/hwpread.cxx
Jeongkyu: I noticed your name here: https://wiki.documentfoundation.org/Language_Teams thought you might be interested in this one. Of course, we could give a try to Google translate or another tool but a human translation is often more right or at least more relevant.
A patch addressing this will be pushed soon.
Jihui Choi committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=188208d93a5d95e1f5eb39294c5e467d6d53edef tdf#91067: Translate Korean comments It will be available in 5.1.0. The patch should be included in the daily builds available at http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More information about daily builds can be found at: http://wiki.documentfoundation.org/Testing_Daily_Builds Affected users are encouraged to test the fix and report feedback.