Hi @tim11_manhhieu. I stopped using or relying on VBA in Inventor a couple years ago, but I do have an iLogic rule on hand that you may find helpful and interesting. It accesses the VBA resources available to Inventor, and digs down into its object/data structure, recording key pieces of information as it goes, then writes all that data out into a text file, sort of like a structured report. It lists all the 'projects', all the components (aka Modules), all the Members (aka Subs / Functions), and all the Arguments (aka input parameters).
This code example does not go into the 'return values' of Members which represent Functions, but when a Member is a Function, you can use its Execute method, which asks for a 'pre-existing' variable as an 'input parameter' that it will then assign the 'return value' to, when it executes. Since this code example is just exploratory, it does not attempt to Call/Run any Functions, or report about their 'return values'.
That code is within the attached text file, for convenience.
Wesley Crihfield

(Not an Autodesk Employee)