Queries not working/ running on live server - php

Question

Well at first you got to believe me on this: the queries I am using are all correct (tested it way to much and also everything works perfectly on the localhost). Lets start explaining my problem: I am running a small application (for fun and learning) and I do a lot of stuff with ajax requests, which works I can see it in the developer tools "sending, those requests go to a function.php file and should run. The code in the function file looks a bit like this:
if (isset($_POST['search'])) {
// Do stuff like running a query
}
All the requests go through the if statement but then all the following queries fail, while correctly writen. So I tried turning on showing erros on the live server but I can't seem to get it done (tried ini_set display errors, with htacces, and messed alot around in the server settings), so I can't see any errors only that the query fails because of this piece of code:
if ($query = mysqli_query($conn, "sql query bla bla")) {
// Dp stuff
} else {
// return error Message
echo "<p style='color:red;'>Something went wrong, please try again!</p>";
}
I get somehting went wrong all the time?
For orientation:
I have a folder, called functions, with multiple function.php files in it all connecting to the database indivitualy, maybe this has something to do with it?
This problem doesn't occurre on only one file but all the function.php files don't work. while If I put php code on origin file itself everything works fine
Hope someone can help me with this, I am out of suggestions
PS my English is not that great hope you will understand! if not let me know or if you need more information also let me know!
Edit
<?php
include_once'/../includes/dbconfig.php';
// If something is posted
if (isset($_POST['search'])) {
$word = stripVariables($_POST['search']);
$querySearch = "SELECT name, description, group_id FROM groups WHERE name LIKE '%$word%'";
$resultSearch = mysqli_query($conn, $querySearch);
$numberSearch = mysqli_num_rows($resultSearch);
// If something is found
if ($numberSearch >= 1) {
$end_result = '';
// Fetch search values, create search results
foreach ($resultSearch as $row) {
global $word;
// Get group values
$name = $row['name'];
$description = substr($row['description'], 0, 40);
$groupId = $row['group_id'];
// Make typed in word bold
$bold = '<b>' . $word .'</b>';
$fullWord = str_ireplace($word, $bold, $name);
// Create list items for each search result
$end_result .= "<li class='search-item'><div class='list-text'>" . $fullWord . "<br><b style='font-size:10pt; font-weight:normal'><span id='group_id'>" . $groupId . "</span> , " . $description ."...</b></div><div class='list-join'><div id='send_request'><p>Send Request</p></div><div><p>Cancel</p></div></div></li>";
}
echo $end_result;
} else {
// Nothing found five error
echo "<li style='color:red; padding: 10px; border: none;'>No results found!</li>";
}
}
// Prevent injections
function stripVariables($input){
$var = trim($input);
$var = strip_tags($var);
$var = stripslashes($var);
$var = htmlspecialchars($var);
return $var;
}
?>
And I use this method with ajax/ javascript
$(".join-inner input[name='submit']").click(function(){
// Get value user input
var inputSearch = $(".join-inner input[type='text']").val();
// Setup datastring
var dataString = "search=" + inputSearch;
// If inputSearch is not empty
if (inputSearch) {
// Ajax call
$.ajax({
type: "POST",
url: "functions/searchGroup.php",
data: dataString,
cache: false,
beforeSend: function(html) {
$('.results').html("");
},
success: function(html){
$('.results').html(html);
}
});
} else {
$('.results').html("<li style='color:red'>Type something to search</li>")
}
return false;
});

Answer 1

Are you sure that $conn is valid ?
$conn = mysqli_connect("localhost", "my_user", "my_password", "my_db");
/* check connection */
if (mysqli_connect_errno()) {
echo("Connect failed: %s\n", mysqli_connect_error());
exit();
}
// Then your code:
if ($query = mysqli_query($conn, "sql query bla bla")) {
// Dp stuff
} else {
// return error Message
echo "<p style='color:red;'>Something went wrong, please try again!</p>";
}