Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"dan duy doc snippets" » "van duy doc snippets", "dan quy doc snippets", "dao duy doc snippets", "dan day doc snippets", "dan duy dac snippets", "dan 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: (((("dan 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: (((("dan duy doc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dan duy doc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dan duy doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.