Perhaps you should try some spelling variations:
"python using java slippers" » "python using data slippers", "python using java slippery", "python using java grippers"
"ngu cao dan snippets" » "ngu ca dan snippets", "ngu cac dan snippets", "ngu cau dan snippets", "ngu cao dang snippets", "ngu cao danh snippets"
"locating bug code snippets" » "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: (((("ngu cao dan snippets") or ("python using java slippers"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("ngu cao dan snippets") OR ("python using java slippers"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( ngu cao dan snippets ) or ( python using java slippers ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("ngu cao dan snippets") or ("python using java slippers"))) or ("locating bug code snippets"))*.