Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"sach thu hoc snippets" » "sach thue hoc snippets", "sach thieu hoc snippets", "sach tham hoc snippets", "sach tu hoc snippets", "sach thu hoi snippets", "sach tru hoc 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 thu hoc 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 thu hoc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( sach thu hoc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("sach thu hoc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.