No less, no more. Just live between code.
Today I did discovering of crawling file shares in SharePoint 2010, for that we need some particular things:
Specify an account to use as default account when crawling content. This account must have read access to the content being crawled. To avoid unpublished versions of documents, ensure that this account doesn’t have full permission on particular location.
We can do that trough explorer or another file manager.
Go to Search administration and click on Content Sources on left panel.
Click on New Content Source:
Set Content source, mainly name and location:
After execution we can see successful crawling:
We can make us sure in crawling log, select from context menu on item:
Go to Search Administration on left panel click on Search Scope, inside click on New Scope:
Next fill name of your new scope out:
Then add new rule, rule type will be Content Source, selected you previous created content source and select include:
After that you must wait for re-crawl which is executed automatically, summary looks similar like this:
As first step you must create search centre site on your site collection, in this case, doesn’t matter which search centre you are choosing, we can work with Basic Search Centre:
Copy url of recently created site and past it to Search Setting on parent site collection settings, and remove “default.aspx”:
Finally go to Search Scope settings and add you scope to “Display Groups” also called as “Search Dropdown”:
Add scope to list:
Test on you main site:
Result:
I hope that helps.
Happy SharePointing! 
Thank you, Martin. This was clear and simpler than Microsoft documentation.