Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"khoa hoc doc snippets" » "hoa hoc doc snippets", "khoa hoc duoc snippets", "khoa hoc do snippets", "khoa hoc doi 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: (((("khoa hoc doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("khoa hoc doc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( khoa hoc doc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("khoa hoc doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.