.card-img-top { object-fit: cover; width: 100%; height: 154px; background: #eee; }
.card { min-height: 230px; }
@media (max-width: 991px) {
    .card-img-top { height: 18vw; max-height:180px; }
}
@media (max-width: 575px) {
    .card-img-top { height: 28vw; max-height:150px; }
}


<style>
.col-5th {
  width: 20%;
  float: left;
  padding-left: 0.5rem;
  padding-right: 0.5rem;
  box-sizing: border-box;
}
</style>