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