Perhaps you should try some spelling variations:
"and computation in refraction errors" » "and computation in refractive errors" (Expand search), "and computation in refractive error" (Expand search), "and computation in refractive erros" (Expand search), "and computational in refraction errors" (Expand search), "of computation in refraction errors" (Expand search), "and computation and refraction errors" (Expand search), "and computation of refraction errors" (Expand search), "and imputation in refraction errors" (Expand search), "and computation sign refraction errors" (Expand search), "and computation in reaction errors" (Expand search)
"using coding python python programming" » "using codigo python python programming" (Expand search), "using codigos python python programming" (Expand search), "using using python python programming" (Expand search), "using coding pythons python programming" (Expand search), "using coding piton python programming" (Expand search), "using coding pitons python programming" (Expand search), "using coping python python programming" (Expand search), "using coating python python programming" (Expand search), "using cooking python python programming" (Expand search)

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("and computation in refraction errors") OR ("using coding python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"and computation in refraction errors\") OR (\"using coding python python programming\"))".
• Removing quotes may allow a broader search: (( and computation in refraction errors ) OR ( using coding python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("and computation in refraction errors") OR ("using coding python python programming"))*.