Any Contracting State or individual claiming to be a victim of a violation of the Convention (individual application) may claim the ECHR's jurisdiction, by alleging a breach by a Contracting State of one of the Convention rights.
Frequently, you will want to find a decision and you will know either the name of the parties, the subject matter, or the year in which it was rendered. There are several sources that will enable you to find a judgment of the European Court of Human Rights.