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