let date = [];
document.querySelectorAll('.organization-table div');
document.querySelectorAll('.organization-table').forEach(el => {
let data = document.querySelectorAll(this + ' div');
date.push(data[0])
});
<div class="organization-table">
<div></div>
<div></div>
<div></div>
</div>
<div class="organization-table">
<div></div>
<div></div>
<div></div>
</div>