Over the past decades, English has become one of the major international languages widely used by many countries. Taiwan, being an international partner, has strived to improve its nationwide English proficiency to advance with international settings. This study investigates the correlation between eye movements of both 1) gazing time (fixation) and 2) frequency of re-reading (number of fixation) the vocabulary of familiar and unfamiliar professional English subjects, for those of both technical and vocational professionals of English as Foreign Language (EFL) participants, while reading professional English, to reading fluency. A newly invented eye chasing device has been used to monitor visual reading progress experiment. Fifteen technical high school students, who have completed Technological and Vocational Education Joint College Entrance Examination of Taiwan (TVE JCEET) in 2014, participated in the experiment. Their reading fluency are measured based on the results of eight questionnaires and answers (Q&A) after reading 8 professional English articles from computer engineering, mechanical, bio-medical, and business subject fields. SPSS 21 was used for descriptive and correlation statistics. Both hypotheses are accepted with results showing that readers from technical background spent more time fixing on reading familiar professional subjects, and mildly inverse relation on frequency of re-reading of professional English contexts. The combination use of multiple visual displays is recommended not only to improve English as foreign language (EFL) users' training and practice but also to enhance quality on professional English readings.