I'm trying to do inventory adjustment for about 6000 items in my inventory by importing an excel file.

However, to initiate the correct import, I try to create export a file in which I will update the quantities and then import. These are the steps I have followed:

1. Inventory - Operations - Inventory Adjustment - Create new adjustment
2. Under products, I select the field and click search more, and then use the checkbox to select all on page
3. It selects 80 items and gives me the option to 'Select all 6000'. 
4. I click select all 6000 and it says selected
5. However in the products selected, Odoo has only selected the 80 from the first page
6. When i select products and search more again, an try to select all, it now gives me the option 'Select all 5920' and then it selects another 80
7. This process keeps repeating with the all count being reduced by 80 every time. It doesn't seem to be selecting all of the 6000 in one go

I'm not able to figure out the issue. And its quite cumbersome to be selecting all from 6000 with 80 reduced each time. Please help.