How can I improve the render lighting?

If you show us some renders maybe someone could help.
Are your models good enough? sometimes the trouble is there, basically the task of geometry is to capture light, so you need beveled edges all around and this is a point somewhat hard to understand .
Try lighting formulas, there are some standard setups for studio lighting, look for them in photography forums.
Hope this helps

Hi, all my models only for 50%

可以改参数，光照的弹射属性。

可以改参数，光照的弹射属性。