Perhaps you should try some spelling variations:
"luan viet code snippets" » "luat viet code snippets", "xuan viet code snippets", "quan viet code snippets", "luan viet co snippets", "luan viet some snippets", "luan viet code slippers"
"dung hung code snippets" » "dung chung code snippets", "dung nhung code snippets", "dung huong code snippets", "dung hung 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: (((("luan viet code snippets") or ("dung hung code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("luan viet code snippets") OR ("dung hung code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( luan viet code snippets ) or ( dung hung code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("luan viet code snippets") or ("dung hung code snippets"))) or ("locating bug code snippets"))*.