Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data snippets"
"duc dung lan snippets" » "duc hung lan snippets", "duc cuong lan snippets", "duc phung lan snippets", "duc dung luan snippets", "duc dung land snippets", "duc dung lam 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: (((("duc dung lan snippets") or ("python using java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duc dung lan snippets") OR ("python using java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( duc dung lan snippets ) or ( python using java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duc dung lan snippets") or ("python using java snippets"))) or ("locating bug core snippets"))*.