Perhaps you should try some spelling variations:
"python using java slippers" » "python using data slippers", "python using java slippery", "python using java grippers"
"phi van viet snippets" » "phi san viet snippets", "phi gian viet snippets", "phi tran viet snippets", "thi van viet snippets", "phi va viet 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: (((("phi van viet snippets") or ("python using java slippers"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("phi van viet snippets") OR ("python using java slippers"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( phi van viet snippets ) or ( python using java slippers ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("phi van viet snippets") or ("python using java slippers"))) or ("locating bug code snippets"))*.