Perhaps you should try some spelling variations:
"dung thang co snippets" » "hung thang co snippets", "cung thang co snippets", "dung thuong co snippets", "dung thong co snippets", "dung tang co snippets", "dung thang o snippets"
"hanh java java snippets" » "hanh 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: (((("hanh java java snippets") or ("dung thang co snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hanh java java snippets") OR ("dung thang co snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hanh java java snippets ) or ( dung thang co snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hanh java java snippets") or ("dung thang co snippets"))) or ("locating bug code snippets"))*.