Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"hoi den toan snippets" » "hoi dien toan snippets", "hoi dan toan snippets", "hoi den tran snippets", "moi den toan snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("hoi den toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hoi den toan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hoi den toan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hoi den toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.