Documents search from another Team Site in the same tenant

[Alpha221]

I have created a Team site with multiple document libraries and added links for the other site's document libraries, and I want to search for documents from other site document libraries. (within the same tenant). Unfortunately, I cannot search documents from other sites' document libraries.
Please can anyone guide me that how I can accomplish this- I am a new user of SharePoint.

[#2]

I started using sharepoint last year.
I have also tried to display the document libraries from another site on a different team site as well, but could not find a way to do so. As a final compromise, I decided to embed the document library by Iframe.

[#3]

Hello @Alpha221

as we texted private with your additional requirement:

I want to search other libraries' from my team site through the search box (Microsoft Search Box). 

It is possible to configure the Microsoft Search Scope:

https://docs.microsoft.com/en-us/microsoftsearch/manage-spo-search-box

> When all your team sites are associated to a hub

Other way is to configure a custom search page with the PnP Modern Search WebParts:

https://docs.microsoft.com/en-us/microsoftsearch/create-search-results-pages

https://microsoft-search.github.io/pnp-modern-search/

> for highly search customization with a free solution

Other way is to configure your own Microsoft Search Vertical. In your vertical you can add the URLs from the libraries, that you want to search: 

https://docs.microsoft.com/en-us/microsoftsearch/manage-verticals

Hope this information and links help you for a good solution.

Regards, Dave