Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"dan van long snippets" » "dan van luong snippets", "dan van dong snippets", "dan van cong snippets", "dang van long snippets", "doan van long snippets", "dao van long 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: (((("python using java snippets") or ("dan van long snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("python using java snippets") OR ("dan van long snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( python using java snippets ) or ( dan van long snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("python using java snippets") or ("dan van long snippets"))) or ("locating bug code snippets"))*.