I am trying to categorizing my pose library into many "sub-libraries" such as mouth, eye, expression. However, blender only keeps the last sub-library selected before closing the file, and loses all the other when the file reopened.

Currently, 2.79

What do I need to do? Is there anything else I have to do to keep other sub-library before closing the file?

Will move to 2.8 after this project. Hopefully, the principal can be transferred.

Thank you very much for your kind help.