select multiple checked box to retrieve data from the database and display the selected data

i want to select multiple check boxes to retrieve data from database and display the checked boxes. but now i am having problem displaying the checked boxes. i have no error but i cannot display my checked data. this is my coding

 <?php
 $sql = "select * from contact_master";
 $query  = mysqli_query($conn, $sql) ;
 while ($row = mysqli_fetch_array($query)){
?>
<tr class="odd gradeX" >
<td><input type="checkbox"  name="chk[]" class="chk-box"/></td>

<td><?php echo $row['Contact_Name'];       ?> <input type="checkbox"  id="myCheck" name="chk[]" class="chk-box" onclick="myFunction()"/></td>   

<td ><?php echo $row['Contact_Phone'];     ?><input type="checkbox"  id="myCheck" name="chk[]" class="chk-box" onclick="myFunction()" /></td>                                                                   <td><?php echo $row['Contact_Email'];      ?><input type="checkbox" id="myCheck"  name="chk[]" class="chk-box" onclick="myFunction()"/></td>                  
<td ><?php echo $row['Contact_Facebook'];  ?><input type="checkbox" id="myCheck"  name="chk[]" class="chk-box" onclick="myFunction()"/></td>                    <td ><?php echo $row['Contact_Wechat'];     ?><input type="checkbox" id="myCheck"  name="chk[]" class="chk-box" onclick="myFunction()"/></td>                  
<td ><?php echo $row['Contact_Whatsapp'];  ?><input type="checkbox" id="myCheck"  name="chk[]" class="chk-box" onclick="myFunction()"/></td>              
<td ><?php echo $row['Contact_Linkin'];    ?><input type="checkbox" id="myCheck"  name="chk[]" class="chk-box" onclick="myFunction()"/></td>                   
<td ><?php echo $row['Contact_Twitter'];   ?><input type="checkbox" id="myCheck" name="chk[]" class="chk-box" onclick="myFunction()"/></td>                             
             <input type="submit" name="submit" value="Submit"/>

//this is how i connect data from the database
<?php

$sql = "SELECT * FROM contact_master";
$result = mysqli_query( $conn, $sql );


if( $result ){
// success! check results
while( $row = mysqli_fetch_assoc( $result )){

$i = 0
{
    $Contact_Name = $row['Contact_Name'];
if(isset($_POST[$Contact_Name])!=NULL)
{
$i = 0; 
$i++;

mysqli_query("select * from contact_master Where Contact_Name = $Contact_Name")or die(mysql_error());
}}}}
$i = 0; 
echo "Selected Contact".$i['Contact_Name']
?>
</html>
</tr>