Perhaps you should try some spelling variations:
"dung ninh cong snippets" » "dung ninh code snippets", "dung vinh cong snippets", "quang ninh cong snippets", "dung dich cong snippets", "dung minh cong snippets", "dung sinh cong snippets", "dung dinh cong snippets"
"locating bug core snippets" » "locating bug code snippets"
"dung java java snippets" » "dung va java 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 ninh cong snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung ninh cong snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( dung ninh cong snippets ) or ( dung java java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung ninh cong snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))*.