wqy-microhei is a very useful chinese fonts, suggest add it to guix.

1. http://wenq.org/wqy2/index.cgi?MicroHei_BigBang_README
2. http://downloads.sourceforge.net/project/wqy/wqy-microhei/0.2.0-beta/wqy-microhei-0.2.0-beta.tar.gz?r=http%3A%2F%2Fwenq.org%2Fwqy2%2Findex.cgi%3FDownload&ts=1484272152&use_mirror=nchc