You cannot modify the property division portions of a divorce. If spousal support is not designated as "non-modifiable," the award can be modified based upon a substantial change in circumstances. A child support award can be modified based upon a substantial change in circumstances. The parenting plan can be modified if modification is in the children's best interest. A joint custody award can be modified if the parents show that they can no longer communicate effectively. A sole custody award can be modified based upon a showing of a substantial change in circumstances.
It depends upon the type of modification you're seeking. Modifications of child support, custody and visitation orders are not uncommon. Other types of modifications are less common but sometimes still possible.
In any event, motions seeking modifications are complicated and require good application of the law to the facts. You should consult with a divorce attorney in your area to discuss the specifics of your case.