Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"sach xa cham snippets" » "sach dao cham snippets", "sach nha cham snippets", "sach bai cham snippets", "sach va cham snippets", "sach ca cham snippets", "sach xa chau 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 ("sach xa cham snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung java java snippets") OR ("sach xa cham snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( sach xa cham snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("sach xa cham snippets"))) or ("locating bug code snippets"))*.