String translation failure in Wordpress+Woocommerce with WPML. Where to look??

Question

Internationalization and localization

Given: WordPress 5.4.4 (from off site in Russian). + WooCommerce. The theme is a child of Storefront.
WPML Multilingual CMS Version 3.7.1 (+ addons: WPML String Translation WPML Translation Management)
Essence: Originally a site in Russian. And all goods. But with the entry into force of the law of January 16, all services must be in Ukrainian. And the customer said to make a website in Ukrainian. Previously, I made a business card site, in 2 languages ​​(Rus + German) with WPML, everything was fine ... Now I installed it, only in the configuration described above. I was sure that everything was fine with the translations, having created several pages, I began to fill in the content (about 200 headings). I thought it was in the hat, but it was in *** ne.
Problem: Did not translate the main system points:
- confirmation and submit buttons, system notification text, breadcrumbs, partially admin panel. BUT if you disable WPML and set the site language to Ukrainian. then everything is displayed as it should.
Through loco translate, I looked at translations of files * .mo * .po - does not find the translation of those same buttons. BUT again, the fields themselves (original) which are in English - everything is there. Which way to look.

Answer 1

Woocommerce requires the WooCommerce Multilingual add-on. If it is there, then the problem is in the wpml settings. If the buttons themselves and everything related to *.po files are not translated, you need to look at the settings of the "localization of themes and plugins" item. And translate everything in line translation.

Answer 2

Thank you.
Suddenly, someone will have such a situation - we look at the files themselves. In my case, it was the wrong name. From what WPML "did not see" the translation. For example. The folder contains the wc-ukr-shipping-l10n-uk.po file - this was the translation, with a caveat - the name is not correct. Added (by analogy) _UA and it turned out this: wc-ukr-shipping-l10n-uk_UA.po After, the translation pulled itself up.
Good luck to all.