https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Flexible_Box_Layout/Basic_Concepts_of_Flexbox

el css

.row{
    margin: 0px;
    display: flex ;
    align-items: center;
}

.panelinhorizontalcenter{
    width:45%;
    margin-left: 28%;
    text-align: left;
}


@media only screen and (max-width: 740px) {
.row{
    display: block ;
    align-items: inherit;
}
}

el htrml

    <div class="row" id="laintro">
        <div class="col-sm-12 col-md-6 wow fadeInUp panelinverticalcenter" data-wow-duration="500ms">

            <div class="panelinhorizontalcenter">
                <h2 class="handwritten">Encontrar tu espacio</h2>
                <p>A tan solo cinco minutos a pie de Miraflores, en Barranco, zona tradicional de bohemia, sana
                    diversión, deliciosos platillos y bebidas exóticas.</p>
                <p>&nbsp;</p>
                <h2 class="textoingles handwritten">Find your place</h2>
                <p class="textoingles">Just five minutes’ walk from Miraflores, in Barranco, traditional bohemian area,
                    healthy fun, delicious dishes and exotic drinks.</p>
            </div>

        </div>

        <div class="col-sm-12 col-md-6 feature-desc wow fadeInUp text-center panelinverticalcenter" data-wow-duration="500ms"
             data-wow-delay="300ms">

            <div class="">
                <img src="img/ocaso_item.jpg" style="max-height: 40vh"/>
            </div>

        </div>

    </div>
    
    

just text

The Flexible Box Module, usually referred to as flexbox, was designed as a one-dimensional layout model, and as a method that could offer space distribution between items in an interface and powerful alignment capabilities. This article gives an outline of the main features of flexbox, which we will be exploring in more detail in the rest of these guides.

a continuacion como resolvi para que dis divs paralelos parezcan del mismo porte aunque tienen contenido distinto
usando bootstrap
aunque ROMPE algunas de las reglas de esa libreria