Perhaps you should try some spelling variations:
"tong thi sio2 snippets" » "trong thi sio2 snippets", "tang thi sio2 snippets", "dong thi sio2 snippets", "tong thi gioi snippets", "tong thi sao snippets", "tong thi sinh snippets", "tong thi sio2 slippers"
"python using a snippets" » "python using a slippers"
"locating bug code snippets" » "locating bug code slippers", "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: (((("tong thi sio2 snippets") or ("python using a snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("tong thi sio2 snippets") OR ("python using a snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( tong thi sio2 snippets ) or ( python using a snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("tong thi sio2 snippets") or ("python using a snippets"))) or ("locating bug code snippets"))*.