Perhaps you should try some spelling variations:
"dung thuy do snippets" » "duong thuy do snippets", "dang thuy do snippets", "dung thu do snippets", "dung thuyet do snippets", "dung thay doi snippets", "dung thuat do 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 thuy do 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 thuy do snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung thuy do snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung thuy do snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.