Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van thi ca snippets" » "van tai ca snippets", "dan thi ca snippets", "van thu ca snippets", "van thi cam snippets", "van thi cua snippets", "van thi cai 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 thi ca 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 thi ca snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van thi ca snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van thi ca snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.