Perhaps you should try some spelling variations:
"dung thanh du snippets" » "dong thanh du snippets", "dang thanh du snippets", "dung thang du snippets", "dung thanh do snippets", "dung thanh tu snippets", "dung thanh de 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 thanh du 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 thanh du snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung thanh du snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung thanh du snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.