Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"thi moi toan snippets" » "thi mon toan snippets", "thi boi toan snippets", "thi gioi toan snippets", "thi mai toan snippets", "thi mo toan snippets", "thi hoai 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: (((("thi moi 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: (((("thi moi toan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( thi moi toan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("thi moi toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.