Perhaps you should try some spelling variations:
"python using java grippers" » "python using data grippers"
"doi ca viet slippers" » "doi va viet slippers", "doi co viet slippers", "doi hoa viet slippers", "doi cua viet slippers", "doi cay viet slippers", "duoi ca viet slippers", "doi ca viet slippery"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("doi ca viet slippers") or ("python using java grippers"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("doi ca viet slippers") OR ("python using java grippers"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( doi ca viet slippers ) or ( python using java grippers ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("doi ca viet slippers") or ("python using java grippers"))) or ("locating bug code snippets"))*.