Perhaps you should try some spelling variations:
"dung ninh du snippets" » "dung vinh du snippets", "quang ninh du snippets", "dung dich du snippets", "dung ninh duc snippets", "dung dinh du snippets", "dung minh duc snippets"
"dung java java snippets" » "dung va java 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: (((("dung ninh du snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung ninh du snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung ninh du snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung ninh du snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.