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