Perhaps you should try some spelling variations:
"viet duong 2 snippets" » "viet huong 2 snippets", "viet dung 2 snippets", "viet cuong 2 snippets", "viet duong _ snippets", "viet duong o snippets", "viet duong co snippets", "viet duong 2 slippers"
"python using java snippets" » "python using data snippets", "python using java slippers"
"locating bug code snippets" » "locating bug code slippers", "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: (((("viet duong 2 snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("viet duong 2 snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( viet duong 2 snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("viet duong 2 snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.