[SalesForce] Apex Query on ContentVersion object and get all record

I called Salesforce support regarding this issue. Changing the Apex class as follows fixes the problem:

public class ConciergeDisplayFamilyMembers
{ 
public Contact currentContact {get;set;}     

public List<Contact> Records
{

    get
    {
        try
        {
            Records = new List<Contact>();
            Records = [SELECT Name,Gender__c,Subscriber_ID__c,Member_ID_suffix__c,Member_ID__c FROM Contact WHERE Subscriber_ID__c = :currentContact.Subscriber_ID__c and RecordTypeId = '012q00000004SAiAAM']; 
        } 
        catch (Exception ex)
        {
              Records = null;
        }
        return Records;
    }
    private set;
}

public ConciergeDisplayFamilyMembers(ApexPages.StandardController sc)
   {
    sc.AddFields(new List<String>{'Subscriber_ID__c'});
    currentContact = (Contact) sc.getRecord();     
    System.debug('***** ' + currentContact );
   }
}

To solve your purpose trigger needs to be invoked on ContentDocumentLink.

When you are uploading the file from File Tab trigger will fire on "ContentVersion" object, but when you are uploading file from Chatter tab you need to write trigger on "ContentDocumentLink" object.Then only you will be able get the Content Document Id.

It seems like a standard feature of salesforce that the triiger on contentVersion doesn't get called when you are uploading the file from File Tab.