getting rows from table based on foreign table's column content in laravel

i have tow tables one

items - id|category|subcategory|make|model. and another table 
machines - id|year|description|photo_path|items_id|and bunch of other columns.

on the front end of website I'm trying to get all the machines that has certain category or subcategory, etc.. how can i use eloquent model to achieve that?

via Chebli Mohamed