Assuming that you're asking about why certain types of events are not present in your audit logs, without knowing the details of your setup I can only speculate as to why that might happen.  You can find short descriptions of the event types in the Admin Guide: http://www.laserfiche.com/support/webhelp/laserfiche/9.1/en-us/adminguide/LFAdmin.htm#Audit_Event_Descriptions.htm, but I'll also give a short explanation:

Any "Purge", "Recycle", or "Restore" event will be related to the recycle bin, so if you have it disabled it's not surprising that you don't see any.

"Write E-File Contents" records modification of the electronic file portion of a document.  If all of your documents are scanned pages, or the electronic files are PDFs or some other format that is not commonly modified, that might be why you don't see any of those.  "Delete E-File" refers to the deletion of the electronic file portion of the document without deleting the document itself; it's not something that necessarily happens often ("Recycle E-File", "Purge E-File", and "Restore E-File" are all related to this same operation, but are only relevant if the recycle bin is enabled).

"Delete Pages", similarly, only happens when an individual page or pages are deleted from a document.  "Restore Page" would require individual pages to have been recycled.

Finally, "Write Alternate E-File" and "Delete Alternate E-File" should never show up unless you have some kind of integration or other application using the SDK that is making use of alternate e-files.  To my knowledge, no Laserfiche software does anything with them at this time.

(If your question was about the emptiness of the lower section of the dialog shown in your screenshot, Chris's explanation of audit reasons is correct).