Perhaps you should try some spelling variations:
"article and nonlinear optical" » "article and nonlinear optics"
"article and nuclear physical" » "article and nonlinear physical", "article and nuclear medical", "article and nuclear optical"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("article and nuclear physical") OR ("article and nuclear physics"))) OR ("article and nonlinear optical"))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"article and nuclear physical\") OR (\"article and nuclear physics\"))) or (\"article and nonlinear optical\"))*".
• Removing quotes may allow a broader search: (((( article and nuclear physical ) OR ( article and nuclear physics ))) or ( article and nonlinear optical ))*.