Add support to get documents by filter

[bhupixb]

Pull Request

Related issue

Fixes #613

What does this PR do?

• Add support to get documents by filter.
• Updatex code samples.

PR checklist

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• [x] Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
• [x] Have you read the contributing guidelines?
• [x] Have you made sure that the title is accurate and descriptive of the changes?

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