Are you always getting redirected to the PDFSearchTip page? If so, a browser hijacker is the reason for these redirects. PDFSearchTip is found to be a browser hijacker that will attempt to commandeer your browser search and homepage towards a fake one. This browser hijacker will send you to dubious websites to get money from you or infect your computer further. It may also monitor your browsing history and prevent you from changing your settings back.
PDFSearchTip is usually installed through bundled software without you knowing. Remove it immediately.