Search only working on front page (index) , not working on other pages

Currently your form looks like:

<form id="search-query">
    <p class="in-english"><a href="http://localhost/hermodswp/?page_id=76">Information in English</a></p>
    <div class="search-box">                
        <div>
            <label class="screen-reader-text" for="s"></label>
            <input type="text" value="sdf" name="s" id="s" style="width: 293px;">
            <input type="submit" id="searchsubmit" value="Sök">
        </div>
    </div>
</form>

Try adjusting your submit action to point to your home_url().

action="<?php echo home_url(); ?>"

You can edit the page in Chrome to see that this works fine.

<form role="search" id="search-query" method="get" action="http://hermodsgymnasiet-develop.kaigan.modxcloud.com/">
    <p class="in-english"><a href="http://localhost/hermodswp/?page_id=76">Information in English</a></p>
    <div class="search-box">        
        <div>
            <label class="screen-reader-text" for="s"></label>
            <input type="text" value="" name="s" id="s" style="width: 293px;">
            <input type="submit" id="searchsubmit" value="Sök">
        </div>
    </div>
</form>