The test sequence block has one test formed by a set of steps arranged in hierarchy. Here you have one test per harness created.
If you have a long list set of steps in your test, you could try to debug your test sequence. Debugging involves setting breakpoints to stop simulation, observing data and test sequence progression, and manually stepping through test steps.
Please have a look at the following link for more details of test sequence debugging:
Hope it helps to solve your question.