Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"sach duc ton snippets" » "sach duoc ton snippets", "sach dung ton snippets", "sach nuoc ton snippets", "sach duc tan 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 duc ton 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 duc ton snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( sach duc ton snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("sach duc ton snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.