"SELECT name FROM wp_venues WHERE name ='".the_field('venue')."' ";
will only return the value of
the_field('venue') which is already known.
"SELECT * FROM wp_venues WHERE name ='".the_field('venue')."' "; will select the whole row with all fields.
Try too use
$wpdb->prepare for security reasons.
$wpdb->get_row you get the whole row as either an object, a numerically indexed array or an associative array. See the codex on get_row.
For example you could do the following:
$row = $wpdb->get_row( $wpdb->prepare("SELECT * FROM wp_venues WHERE name = %s", the_field('venue')));
echo "Name: ".$row->name."\n";
echo "Capacity: ".$row->capacity."\n";
echo "Image: ".$row->image."\n";
echo "Description: ".$row->description."\n";
Try what is mentioned in the codex : http://codex.wordpress.org/Class_Reference/wpdb#Show_and_Hide_SQL_Errors and turn on
WP_DEBUG in wp-config.php.
In addition :
$wpdb->last_query can be looked up to show the last query used. Retrieve the query, that is actually executed and try this query manually and see which results there are.