Perhaps you should try some spelling variations:
"python using java slippers" » "python using data slippers", "python using java grippers"
"tu phan van slippery" » "tu pham van slippery", "tu thanh van slippery", "tu luan van slippery", "thu phan van slippery", "tu nhan van slippery", "tu phat van slippery"
"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: (((("tu phan van slippery") or ("python using java slippers"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("tu phan van slippery") OR ("python using java slippers"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( tu phan van slippery ) or ( python using java slippers ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("tu phan van slippery") or ("python using java slippers"))) or ("locating bug code snippets"))*.