Perhaps you should try some spelling variations:
"phi truong o snippets" » "thi truong o snippets", "phi thuong o snippets", "phi trong o snippets", "phi truong bo snippets", "phi truong v snippets", "phi truong _ snippets"
"python using java snippets" » "python using data 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 truong o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("phi truong o snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( phi truong o snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("phi truong o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.