Perhaps you should try some spelling variations:
"python missing data snippets" » "python using data snippets"
"locating bug core snippets" » "locating bug code snippets"
"khoa dan a snippets" » "khoa dang a snippets", "hoa dan a snippets", "khoa can a snippets", "khoa dan ca snippets", "khoa dan va snippets", "khoa dan ap 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: (((("khoa dan a snippets") or ("python missing data snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("khoa dan a snippets") OR ("python missing data snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( khoa dan a snippets ) or ( python missing data snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("khoa dan a snippets") or ("python missing data snippets"))) or ("locating bug core snippets"))*.