Yes, there are several techniques to improve your critical thinking skills using previous years' papers for Commerce. Here are a few suggestions:

1. Analyze the questions: Carefully read and analyze the questions from previous years' papers. Identify the key concepts and understand what the question is asking for.

2. Identify patterns: Look for any recurring patterns or themes in the questions. This will help you understand the areas that are frequently tested and give you an idea of what to focus on while studying.

3. Compare and contrast: Practice comparing and contrasting different concepts or theories. Look for similarities and differences between different topics or case studies mentioned in the previous years' papers.

4. Evaluate arguments: Critically evaluate the arguments or solutions provided in the previous years' papers. Assess the strengths and weaknesses of the arguments, and consider alternative perspectives or counterarguments.

5. Solve problems: Solve the numerical or case study-based problems given in the previous years' papers. This will help you develop your problem-solving skills and apply theoretical concepts to real-life scenarios.

6. Practice time management: Set a time limit for each question while solving the previous years' papers. This will help you improve your time management skills and prepare for the actual exam conditions.

7. Seek feedback: After attempting the previous years' papers, seek feedback from your teachers, mentors, or peers. Discuss the answers and reasoning behind each question to gain different perspectives and improve your critical thinking approach.

Remember, critical thinking is a skill that improves with practice, so make sure to regularly engage with previous years' papers and apply these techniques to enhance your skills.