Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"khan toan du snippets" » "khanh toan du snippets", "khan than du snippets", "thanh toan du snippets", "khan tran duc snippets", "khan toan cau 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: (((("khan toan du snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("khan toan du snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( khan toan du snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("khan toan du snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.