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