Is it OK to mix potting soil with topsoil?

Hello there, I'm curious about a gardening question I've been pondering. I'm planning to start a new flower bed and I'm wondering if it's okay to mix potting soil with topsoil. I've heard that potting soil is rich in nutrients and helps plants grow better, but I'm also concerned about its ability to drain properly when mixed with topsoil. Can you give me your thoughts on this matter? Would the mixture provide the right balance of nutrients and drainage for my flowers? Thanks in advance for your help!