If your site is in 4 languages, Google needs to know which version to show whom.
Hreflang syntax
<link rel="alternate" hreflang="uz" href="https://site.uz/uz/"> <link rel="alternate" hreflang="ru" href="https://site.uz/ru/"> <link rel="alternate" hreflang="en" href="https://site.uz/en/"> <link rel="alternate" hreflang="x-default" href="https://site.uz/">
Language codes
ISO 639-1: uz, ru, en, kk, tg. With region: en-GB, en-US.
In sitemap
Even better — declare in sitemap.xml via xhtml:link.