Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"luan viet he snippets" » "luat viet he snippets", "xuan viet he snippets", "quan viet he snippets", "luan viet ha snippets", "luan vien he snippets", "luan viet ve 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: (((("luan viet he snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("luan viet he snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( luan viet he snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("luan viet he snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.