Here is how to solve this problem.

We have to modify the current robot.txt file directly in Odoo.

To do so, activate the developer mode.

Then in general settings, go in Technical, then “Views” under the “User interface” tab.
Search for a view named “robots” and modify the architecture.

By default you have the following content

“User-agent: *”

We are going to erase this line and add the following ones:

“User-agent: Googlebot
Disallow:
User-agent: Googlebot-image
Disallow:”

Save the changes and now Google should be able to access all your website’s pages.