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