Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"cuon sach do snippets" » "duong sach do snippets", "cuoc cach do snippets", "co sach do snippets", "cuon sach dao snippets", "cuon sach doi snippets", "cuon sach de 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 ("cuon sach do snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung java java snippets") OR ("cuon sach do snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( cuon sach do snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("cuon sach do snippets"))) or ("locating bug code snippets"))*.