I found some equal questions, but no answers are available in Magento 2.
Any one can tell me how to enable or add layered navigation to search result page in Magento 2.
Any help would be appreciated.
It's tied to the attribute settings:
If you need show layered navigation for some attribute then please enable it in backend. Go to stores > attributes > product, find and open needed attribute (for example price) and on tab "Storefront Properties" configure "Use in Search Results Layered Navigation" - Yes