Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"duc duy doc snippets" » "duc huy doc snippets", "duc quy doc snippets", "duc dung doc snippets", "duc day doc snippets", "duc duy dac snippets", "duc duy dot 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: (((("duc duy doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duc duy doc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duc duy doc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duc duy doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.