Fix BM25ContentFilter documentation to use language parameter instead of use_stemming (#1152)

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: UncleCode <unclecode@kidocode.com>

docs/md_v2/core/fit-markdown.md

@@ -137,7 +137,7 @@ if __name__ == "__main__":
   - Higher → fewer chunks but more relevant.  
   - Lower → more inclusive.  
 
-> In more advanced scenarios, you might see parameters like `use_stemming`, `case_sensitive`, or `priority_tags` to refine how text is tokenized or weighted.
+> In more advanced scenarios, you might see parameters like `language`, `case_sensitive`, or `priority_tags` to refine how text is tokenized or weighted.
 
 ---
 
@@ -242,4 +242,4 @@ class MyCustomFilter(RelevantContentFilter):
 
 With these tools, you can **zero in** on the text that truly matters, ignoring spammy or boilerplate content, and produce a concise, relevant “fit markdown” for your AI or data pipelines. Happy pruning and searching!
 
-- Last Updated: 2025-01-01
+- Last Updated: 2025-01-01

docs/md_v2/core/markdown-generation.md

@@ -187,7 +187,7 @@ from crawl4ai import CrawlerRunConfig
 bm25_filter = BM25ContentFilter(
     user_query="machine learning",
     bm25_threshold=1.2,
-    use_stemming=True
+    language="english"
 )
 
 md_generator = DefaultMarkdownGenerator(