Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"qua di toan snippets" » "qua vi toan snippets", "qua dien toan snippets", "qua dich toan snippets", "qua da toan snippets", "qua dieu toan 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: (((("qua di toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("qua di toan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( qua di toan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("qua di toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.