Custom taxonomy
$tax_query = array( array( 'taxonomy' => 'area', 'terms' => 'area-example', 'field' => 'slug', ), array( 'taxonomy' => 'modality', 'terms' => 'modality-example', 'field' => 'slug', ), );
$tax_query = array( array( 'taxonomy' => 'area', 'terms' => 'area-example', 'field' => 'slug', ), array( 'taxonomy' => 'modality', 'terms' => 'modality-example', 'field' => 'slug', ), );