Perhaps you should try some spelling variations:
"dung hieu con snippets" » "dong hieu con snippets", "dung tieu con snippets", "trung hieu con snippets", "dung dieu con snippets", "dung lieu cong snippets", "dung hien cong 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 hieu con 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 hieu con snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung hieu con snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung hieu con snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.