Perhaps you should try some spelling variations:
"dung sinh cong snippets" » "duong sinh cong snippets", "dang sinh cong snippets", "dung ninh cong snippets", "dung minh cong snippets", "dung trinh cong snippets", "dung chinh 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: (((("dung sinh 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: (((("dung sinh cong snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung sinh cong snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung sinh cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.