Photoionization absorption model search for the time-averaged spectra of 1H 1934-063 (a), RE J1034+396 (b), PG 1244+026 (c), PG 1211+143 (d), I ZW 1 (e) and IRAS 17020+4544 (f) over the baseline model (continuum or plus WAs). The color illustrates the statistical improvement after adding an absorption component with a line width of 1500 km s⁻¹ (except PG 1211+143 with σ_v = 500 km s⁻¹). The purple, green, and yellow contour lines correspond to 99.73%, 95.4%, and 68.3% confidence level. The solution with the most significant detection is marked by a red cross and the secondary detection is marked by a blue diamond, while it may not be the final solution, as another potential solution can be the most significant detection during the spectral modeling when the line width σ_v is free to vary.