Perhaps you should try some spelling variations:
"giao trinh code snippets" » "giao trinh cong snippets", "giao trinh co snippets", "giao trinh cad snippets", "giao trinh code 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"

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: (((("python using a snippets") or ("giao trinh code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("python using a snippets") OR ("giao trinh code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( python using a snippets ) or ( giao trinh code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("python using a snippets") or ("giao trinh code snippets"))) or ("locating bug code snippets"))*.