Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"sach khoi he snippets" » "sach hoi he snippets", "bach khoa he snippets", "cach thoi he snippets", "sach khoa he snippets", "sach khoi de snippets", "sach khong he 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: (((("sach khoi he snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("sach khoi he snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( sach khoi he snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("sach khoi he snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.