如何在yoast SEO中添加自定义分类到元字段？

I have a wordpress 4.2.1 based website with Yoast wordpress SEO plugin. In this site I have several custom posts types such as "publications" with some custom taxonomies "keywords, authors" all are made by custom post type UI plugin. When viewing the page source of articles published in that custom post type the code shows meta properties like:I have a wordpress 4.2.1 based website with Yoa