You'd better find an agency to do this. For foreign-related trademarks, it's best to conduct a search first. Non-professionals can't do the search, otherwise all subsequent work will be in vain.

For notarization, you need to go to the Council for the Promotion of International Trade for notarization, and for certification, you need to go to the embassy. In some countries, registered trademarks only require notarization, while others require notarization and certification.

Domestic trademarks are relatively simple and you can apply for them yourself. For foreign ones, it is better to find an agency. It will be easier to deal with any review opinions later.

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