Thank you for your effort. Using ending of surname for search is something I have never tried. I will surely try some different combinations.
Unfortunately I am aware of these records, which are poorly indexed from microfilms. I have browsed microfilm images for Darda and surrounding places and find several mistakes in these records.
1. András Kovács, 1847, Hercegszöllős, Ferentz Kovács & Theréz Rozsgonyi
born on 17 Jun 1847 in Darda, not Hercegszöllős (now Kneževi Vinogradi)
https://familysearch.org/pal:/MM9.3.1/TH-1942-28193-9763-42. Katalin Kováts, 1851, Hercegszöllős, Ferentz Kováts & Theréz Rosgónyi
born on 4 Mar 1851 in Darda, not Hercegszöllős (now Kneževi Vinogradi)
https://familysearch.org/pal:/MM9.3.1/TH-1942-28193-9507-423. Catharina Kovács, 3 Oct 1854, Dárda, Franciscus Kovács & Theresia Rosgonyi
correctly indexed
https://familysearch.org/pal:/MM9.3.1/TH-1942-28193-8515-424. Adamus Kovács, 1854, Hercegszöllős, Franciscus Kovács & Theresia Roszgonyi
switched pages during indexing, duplicate, it is really Catharina (number 4)
5. Maria Kováts, 25 Dec 1857, Dárda, Franciscus Kováts & Theresia Rosgonyi
correctly indexed
https://familysearch.org/pal:/MM9.3.1/TH-1942-28193-8435-476. Friderich Kováts, 25 Dec 1857, Dárda, Franciscus Kováts & Theresia Rosgonyi
twin brother, wrong name, correct: Henricus
https://familysearch.org/pal:/MM9.3.1/TH-1942-28193-8435-477. Katalin Kovacs, 27 Aug 1860, Dárda, Franciscus Kovacs & Theresia Dosgónyi
switched pages during indexing, wrong name and sex, correct: Rosalia
https://familysearch.org/pal:/MM9.3.1/TH-1971-28193-10901-51