1. Look for witnesses: You can ask the shops around the jewelry store or the streets nearby to see if anyone saw what happened.

2. Looking for evidence: You can search the environment around the jewelry store to see if it is possible to collect relevant evidence, such as photos and videos.

3. Find a reliable witness: You can ask the staff in the jewelry store to see if anyone saw or knew about it.

4. Find reliable evidence: bills, invoices and vouchers can be collected. Jewelry store, and jewelry store related records, to see if there is reliable evidence to support evidence collection.