Customer's question:

In the mobile version of my WordPress theme, there is a search bar visible once the hamburger menu clicked.

Question 1:

When I search there, the prases in English appear for example "search results for" that I want to translate into my language. Where can I find it? 

Answer 1: 

Use any plugin for making translations in WordPress. We recommend Loco Translate -> https://wordpress.org/plugins/loco-translate/ 

Then you may search for any untranslated phrase and add the translation of it with your language, like in the example below:

Question 2:

How to remove the search from the sidebar?

Answer 2:

You can remove the search widget by removing it from the sidebar "Off Canvas".  Go to Appearance -> Widgets and look for Off-canvas sidebar.

Learn more:

• How to translate a WordPress theme?