[improve][doc] improve the wiki Pulsar Improvement Proposal (PIP) (#20917)

diff --git a/pip/README.md b/pip/README.md
index c268f8a..1ea4bf2 100644
--- a/pip/README.md
+++ b/pip/README.md
@@ -90,7 +90,7 @@
 You can the view list of PIPs previously managed by GitHub wiki or GitHub issues [here](https://github.com/apache/pulsar/wiki#pulsar-improvement-proposals)
 
 ### List of PIPs
-1. You can view all PIPs (besides the historical ones) as the list of Pull Requests having title starting with `[pip][design] PIP-`. Here is the [link](https://github.com/apache/pulsar/pulls?q=is%3Apr+title%3A%22%5Bpip%5D%5Bdesign%5D+PIP-%22) for it. 
+1. You can view all PIPs (besides the historical ones) as the list of Pull Requests having title starting with `[improve][pip] PIP-`. Here is the [link](https://github.com/apache/pulsar/pulls?q=is%3Apr+title%3A%22%5Bpip%5D%5Bdesign%5D+PIP-%22) for it. 
    - Merged PR means the PIP was accepted.
    - Closed PR means the PIP was rejected.
    - Open PR means the PIP was submitted and is in the process of discussion.