Perhaps you should try some spelling variations:
"co duc hieu snippets" » "co doc hieu snippets", "co duc hien snippets", "co thuc hieu snippets", "co duoc hieu snippets", "cao duc hieu snippets", "do duc hieu snippets", "co duc hieu slippers"
"python using a snippets" » "python using a slippers"
"locating bug code snippets" » "locating bug code slippers", "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: (((("co duc hieu snippets") or ("python using a snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("co duc hieu snippets") OR ("python using a snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( co duc hieu snippets ) or ( python using a snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("co duc hieu snippets") or ("python using a snippets"))) or ("locating bug code snippets"))*.