Start with the product type
Use a concrete type such as running shoes, zip hoodie or small shoulder bag. Add one useful constraint: intended use, material, dimensions or a model reference.
Change one thing at a time
If results are too broad, add a feature. If there are few relevant results, remove a restrictive word or try a simpler product name. Category browsing can help when you do not know the right wording.
Compare like with like
Open a small number of relevant listings and compare the same fields: measurements, materials, variant and stated price. Check additional charges and current service terms before making a purchase decision.