There are a few reasons why Q&A pairs may not appear in the Content Library:

• Content Library moderation is turned on, and your content is in moderation, pending review. See Setting Up and Using Content Library Moderation for more information.
• The save options for the Content Library have been turned off at the instance level, project level, or question level. See Saving Q&A Content to the Content Library from Projects for more information.
• The project that the Q&A pairs are in has not yet been marked complete.