Hello All
In odoo V13 when you create Inventory adjustment record and if you select no products on product field then you will get all product which have some quantity in your main warehouse location.if product have negative stock in your warehouse location then also it will show in all product list.

But if you have product which have product quantity is zero then it will not show in product list you need to select particular product with help of create button.

Hope this will help.

Thanks 
Husain

I'm not sure is it the same problem as same as me.

My problem is I cannot see any products for selection when try to do Inventory Adjustment.
Finally, I found this documentation, then I see what cause the problem.

https://www.odoo.com/documentation/user/13.0/inventory/overview/process/initial_stock.html

All of products have to be "Storable Product" for storing in warehouse. I am very new to Odoo, so I created all products to be "Consumable Product" at the first.

I have changed all products those will be stored in warehouse to be "Stolable Product", then the products are appears in Inventory Adjustment record perfectly!

try this

https://www.youtube.com/watch?v=GvCSJLEW_6M