"more narrow than" is correct and usable in written English.
You can use it to compare two things, for example: This street is much more narrow than that one.
"And I told her, 'No, ma'am, I'm more narrow than that.
I know that the demographics for "prestige television" were often more narrow than the coverage about them suggested, the ratings all going to your CSIs and NCISes.
The exclusion of tenants means the bill "is going to be much more narrow" than the laws and policies in other cities, like Los Angeles and San Francisco, she said, adding, "I just don't see it covering that many people".
"Our audience in the United States was a little bit more narrow than we wanted, but the Canadian numbers are really strong, and the overseas reaction has exceeded our expectations," he said.
The cells of organisms also contain solutions of dissolved ions, but the range of salinity that occurs in tissues is more narrow than the range that occurs in nature.
The gap between a philosemite and an antisemite is more narrow than a slice of matza because they both treat Jews as something not quite human, as something Other.
"I.B.M.'s footprint is more narrow today than it was when I started.
"Castles of Steel" is a more narrow chronicle than "Dreadnought," focused on the naval battles of the war.
The two have been discussing a possible measure that would expand background checks to gun show purchases and online sales – a more narrow field than most Democrats want.
It would probably take a more narrow approach than the Kucinich amendment, cutting off spending for specific actions like Predator strikes.
It is also found that the diameter of the superlong aligned SWNTs is smaller with more narrow distribution than that of random nanotubes.
