Can't change label on dropbox

Hello! I have site on russian language and use your plugin: dropbox with sizes. The label of dropbox is ‘Filters:’ (text in english). I have arussian translate (in .mo,.po and .pot files) of label ‘filters:’ but it doesn’t work, this text doesn’t change. And so the users of my site see one english word on russian site. It isn’t good, how i can change the label?

https://wordpress.org/plugins/yith-woocommerce-ajax-navigation/