难怪

難怪
nánguài
  1. (it's) no wonder (that...)
  2. (it's) not surprising (that)

CEDICT

Entry Composition

1 难 nán
  1. difficult (to...)
  2. problem
  3. difficulty
  4. difficult
  5. not good
=2 怪 guài
  1. bewildering
  2. odd
  3. strange
  4. uncanny
  5. devil
  6. monster
  7. to wonder at
  8. to blame
  9. quite
  10. rather
=2 怪 guài variant of 怪 guài