I'm trying to add multiple query string values at the current url but i'm not understanding how to do it.
I'm using express and Nodejs.
I've created a route that can read the values
router.get('/posts', (req, res) => {
    Post.find({}).populate('files').exec((err, posts) => {
        if(err){
            res.redirect('/');
            console.log(err);
        } else {
            console.log(req.query)
            res.render('home');
        }
    });
});
and in the home page i've set some links that add query values
<a href="?Value1=1">Value1</a>
<a href="?Value2=2">Value2</a>
<a href="?Value3=3">Value3</a>
but each time that i click one of them the url resets the query string and add the query value of the cicked link.
So how can i concatenate them?