Study the QC Database Reference. The information you are looking for is in there.
The Functional Groups Diagrams show you relationships between tables for different functional groups (tests, Requirements, Bugs, etc).
The Project Data Tables section provides the information about individual tables. If you look at that, it will tell you what data the table holds. If you look at the Columns info for a table, it will tell you all the columns in the table. Usually there is a column in the table holding the link information between that table and another table. Look at the TEST Table. Look at the Description data in the Columns table. Is there a field that holds information from the ALL_LISTS table there?