Perhaps you should try some spelling variations:
"dung trung chap snippets" » "dung trong chap snippets", "quang trung chap snippets", "truong trung chap snippets", "dung trung cap snippets", "dung trung ha snippets", "dung tranh chap 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 trung chap 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 trung chap snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung trung chap snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung trung chap snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.