Perhaps you should try some spelling variations:
"dang nhap cong snippets" » "dang nhat cong snippets", "dung nhan cong snippets", "danh nhan cong snippets", "dang phap cong snippets", "dang phap chong snippets", "dang phan cong 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: (((("dang nhap cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dang nhap cong snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dang nhap cong snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dang nhap cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.