Perhaps you should try some spelling variations:
"duong manh java snippets" » "duong van java snippets", "duong manh va snippets", "duong manh java slippers"
"dung luan code snippets" » "dung luan cong snippets", "dung luan che snippets", "dung luan de snippets", "dung luan code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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 luan code snippets") or ("duong manh java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung luan code snippets") OR ("duong manh java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung luan code snippets ) or ( duong manh java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung luan code snippets") or ("duong manh java snippets"))) or ("locating bug code snippets"))*.