Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"tung van toan snippets" » "trung van toan snippets", "tang van toan snippets", "dung van toan snippets", "tung van tuan snippets", "tung van tan snippets", "tung van thanh 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 java java snippets") or ("tung van toan snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung java java snippets") OR ("tung van toan snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( tung van toan snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("tung van toan snippets"))) or ("locating bug code snippets"))*.