QtCreator: Completion and HighLighter sometimes don't work

[Please_Help_me_D]

Hi,

When I working with execution files everything is ok.
But sometimes in header files (usually headers with template functions) I can see that completion and highlighter don't work (usually with 3rd parties libraries methods). You can see black font on the picture.

What is the problem and is it possible to fix it? It get really annoying