This will depend on what type of fields you’re using. I’m assuming that you’re using some type of field that’s stored as text, like a text field or a single select field.
$args = array(
'post_type' => 'salesperson',
'meta_query' => array(
'relation' => 'AND',
array(
'key' => 'country',
'value' => $country
),
array(
'key' => 'state',
'value' => $state
),
array(
'key' => 'industry',
'value' => $industry
)
)
);
$query = new WP Query($args);