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