Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"danh viet cham snippets" » "anh viet cham snippets", "ninh viet cham snippets", "nang viet cham snippets", "danh viet nam snippets", "danh viet ha snippets", "danh viet phan 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 ("danh viet 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 ("danh viet cham snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( danh viet cham snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("danh viet cham snippets"))) or ("locating bug code snippets"))*.