Provided is a process of enhanced oil recovery from an oil reservoir of an underground formation by using a compound of formula (I) to inhibit the phenomena of retention of anionic surfactants within an oil-bearing reservoir, such as a carbonate or clay reservoir: R—O—(—CH2—CH(—CH3)—O—)m—(—CH2—CH2—O—)n—H, wherein: R is a hydrocarbon-based group comprising from 6 to 40 carbons; m ranges from 0 to 20; n is greater than m and ranges from 5 to 40.