I looked for answers to many similar questions.

Google Cloud Vision to detect only one language

And I found this page.

From what I understand, the way to solve this problem was:

      const result = await axios.post(
        `${API.TEXT_ENDPOINT}?key=${process.env.API_KEY}`,
        {
          requests: [
            {
              image: {
                content: canvas
                  .toDataURL()
                  .replace(/^data:image\/[a-z]+;base64,/, ""),
              },
              features: [
                {
                  type: "TEXT_DETECTION",
                  maxResults: 1,
                },
              ],
              imageContext: {
                languageHints: ["ko"],
              },
            },
          ],
        },
        {
          headers: {
            "Content-Type": "application/json",
          },
        },
      );

However, if I write this way, it seems that English is recognized unconditionally along with the language I have designated.

This page says;

List of languages to use for TEXT_DETECTION. In most cases, an empty value yields the best results since it enables automatic language detection. For languages based on the Latin alphabet, setting languageHints is not needed. In rare cases, when the language of the text in the image is known, setting a hint will help get better results (although it will be a significant hindrance if the hint is wrong). Text detection returns an error if one or more of the specified languages is not one of the supported languages.

How can I make the vision APi detect only one language? (especially not to detect English!!)