Yes, there are several techniques you can use to improve your problem-solving accuracy using previous years' papers for Commerce. Here are a few suggestions:

1. Familiarize yourself with the exam pattern: Look for patterns in the types of questions asked, the weightage given to different topics, and the format of the questions. This will help you understand what to expect in the actual exam and how to prepare accordingly.

2. Identify common topics and concepts: Analyze previous papers to identify the most frequently asked topics and concepts. Focus on understanding these thoroughly and practice solving related problems to improve your accuracy.

3. Time yourself: Set a time limit for each question or section while practicing with previous years' papers. This will help you improve your speed and accuracy, as time management is crucial during the actual exam.

4. Review and analyze your mistakes: After solving each paper, carefully review and analyze your mistakes. Identify the areas where you made errors and work on improving your understanding of those topics. This will help you avoid similar mistakes in the future.

5. Create a revision plan: Once you have solved a significant number of previous years' papers, create a revision plan based on the topics you found challenging or frequently appeared in the papers. Allocate more time to these topics during your revision to strengthen your understanding and problem-solving skills.

6. Seek guidance if needed: If you face difficulties in solving certain types of problems or understanding specific concepts, seek guidance from your teachers, classmates, or online resources. Collaborating with others and discussing problems can provide different perspectives and enhance your problem-solving skills.

Remember, consistent practice and a focused approach are essential to improve your problem-solving accuracy.