Perhaps you should try some spelling variations:
"dung luan code snippets" » "dung luan cong snippets", "dung luan che snippets", "dung luan de snippets", "dung luan code slippers"
"van quy code snippets" » "van quy che snippets", "van duy code snippets", "van quan code snippets", "van quy code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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: (((("van quy code snippets") or ("dung luan code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("van quy code snippets") OR ("dung luan code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van quy code snippets ) or ( dung luan code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van quy code snippets") or ("dung luan code snippets"))) or ("locating bug code snippets"))*.