If I understand your question, you are asking whether a plaintiff seize your state tax refund to satisfy a judgment against you. The answer is yes, but only after a Request and Writ for Garnishment is filed. A Request and Writ for Garnishment (in this case) is essentially a document that states that the Plaintiff has a valid judgment for monetary damages against you, and that to date it has not been satisfied. It also states that the State of Michigan is in control of funds that belong to the Defendant (you) and that should, in order to satisfy the judgment, be paid to the Plaintiff.
You will know when the filing of the Request and Writ for Garnishment has been filed because the Plaintiff is required to serve it upon you within 7 days after serving it on the state treasurer. Also, you will get a notice from the state indicating that your funds have been intercepted pursuant to the Garnishment. You can, should you so choose, object to the Request and Writ for Garnishment within 14 days of your notification of the Garnishment.
Finally, as to whether the entire refund may be taken, it depends on the amount of the judgment. In theory, the answer is yes. For example, if the judgment was for $500.00 and your state tax return was for $450.00, assuming none of the judgment has been paid to date, then yes, the entire tax return would be subject to seizure.