Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"ngu luan can snippets" » "ngu lap can snippets", "tu luan can snippets", "ngu van can snippets", "ngu luan van snippets", "ngu luan san snippets", "ngu luan han 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 luan can snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("ngu luan can snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( ngu luan can snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("ngu luan can snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.