How to fix SQLite not working during build Unity?

I am making a game in Unity where I'd like to use SQLite database for saving readonly data effectivly. Everything is fine in the Editor, but when I build it to windows, it simply couldn't read from it. I tried everything, the path is in the StreamingAssets, I checked that my database is not empty, I have all the neccessary .dll files, I even tried with different versions, from different sources. I also tried that my program, even after build will find a simple txt file next to the database, so it's not matter of the datapath. I must use database, because I need a dozens of data that is readonly and have been written manually. Also I want a flexible and dynamic way to modify my data during playtime. Here is my code, I have multiple functions handling the database, but this the one that's relevant here:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;
using Mono.Data.Sqlite;
using System.Data;
using Mono.Data;
using System.IO;
public class DataBaseHandler {
  public static Record FindRecord(string database, string table, List<string> fields, string feltetel)
  {
    Record record = new Record(new List<string>());
    string conn = "URI=file:" + System.IO.Path.Combine(Application.streamingAssetsPath, database + ".db");
    IDbConnection dbconn;
    dbconn = (IDbConnection)new SqliteConnection(conn);
        dbconn.Open(); 
        IDbCommand dbcmd = dbconn.CreateCommand();
        string field = "";
        foreach (var item in fields)
        {
            if (item == fields[fields.Count - 1])
            {
                field = field + item + " ";
            }
            else
            {
                field = field + item + ", ";
            }

        }
        //Debug.Log(field);
        string sqlQuery = "SELECT " + field + "FROM " + table + " WHERE " + feltetel;
        dbcmd.CommandText = sqlQuery;
        IDataReader reader = dbcmd.ExecuteReader();

        while (reader.Read())
        {
            for (int i = 0; i < fields.Count; i++)
            {
                record.sor.Add(reader.GetString(i));
            }
        }

        reader.Close();
        reader = null;
        dbcmd.Dispose();
        dbcmd = null;
        dbconn.Close();
        dbconn = null;
        return record;
}
}

Record is just a simple class, but I will show you:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Record
{
public List<string> sor;

public Record(List<string> sor)
{
    this.sor = sor;
}

public Record()
{
}
}

Also, I have every neccessary plugins in my folder. Please help me, this drives me crazy, I have been looking for the solution for a week now.