can't seem to
Be apparently unable to, as in No matter how hard I try, I can't seem to concentrate on this book. This phrase gives added emphasis to a negative statement, as in the example. [Late 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.