Lawson Table Relationship Question

Hello, I'm new to Lawson data. I have been provided 5 Lawson tables and only 5 tables in a data warehouse to report from.

I'm hoping to get help understanding how to link them including which fields to link on, any composite joins, etc. I found some ERD's online, but couldn't find one that would fully visualize what I'm trying to do.

The tables I need to link for reporting include:
APINVOICE
APDISTRIB
APPAYMENTS
APVENMAST
TERMS

Help appreciated. Thank you!
Trevor