Perhaps you should try some spelling variations:
"cong danh viet snippets" » "cuong danh viet snippets", "cong dan viet snippets", "cong thanh viet snippets", "cong anh viet snippets", "cong ninh viet snippets", "cong nang viet snippets", "cong danh viet slippers"
"dung java java snippets" » "dung va java snippets", "dung java java slippers"
"locating bug code snippets" » "locating bug code slippers", "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: (((("cong danh viet snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cong danh viet snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cong danh viet snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cong danh viet snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.