This simple understanding is that there are fuzzy options and precise options. For example, among the "rings" and "rings (jewelry)" you sent, the ring (jewelry) is a precise choice. For example, if you make jewelry, then Just choose rings (jewelry), but there are some "rings" that are not used for jewelry, so the range of selecting "rings" alone increases, but the fuzzy options are not particularly accurate for specific products.

It is also the 14th category, small items of headwear jewelry. This item includes various kinds of precious metal jewelry, which are all headwear jewelry. The scope is relatively large, but it is not accurate, so it is understood as a fuzzy option. If we If we are making a variety of products, then it is better to choose a range. If we are just making hairpins, for example, it would be more accurate to choose hairpins directly.