docs: add related projects section to README files

Author: Anonymous Committer

README.md

@@ -85,6 +85,13 @@ Learn more about the project, data sources, and commercial integration opportuni
 
 ---
 
+## 🔍 Related Projects
+
+### Just Serp API
+Need search engine data? Check out [Just Serp API](https://justserpapi.com/) — a high-performance SERP API providing structured data from Google, Bing, and other search engines.
+
+---
+
 ## 📬 Contact Us
 
 If you have any questions, feedback, or partnership inquiries:

README.zh-CN.md

@@ -84,6 +84,13 @@ print(has_next_page)
 
 ---
 
+## 🔍 相关项目
+
+### Just Serp API
+如果您需要搜索引擎数据，请访问 [Just Serp API](https://justserpapi.com/) — 高性能的 SERP API，提供来自 Google、Bing 等搜索引擎的结构化数据。
+
+---
+
 ## 📬 联系我们
 
 如有任何问题、反馈或合作意向，欢迎联系：