You should not self medicate but get an appointment to see an endocrinologists who could measure your hormone levels and discuss matters with you in a consultation and treat if necessary with Tamoxifen, other anti estrogens or recommend a referral to a good surgeon.
In clinical trials Tamoxifen resolved gynecomastia in 80% of cases. That said the trials involved small numbers of men and were of an uncontrolled nature, so those results are questionable and have not been validated by larger controlled studies.
Tamoxifen can only reduce glandular mass via a lowering of the effects of estrogen. For this reason it would only help reduce/resolve gynecomastia of a glandular variety where estrogen is too high.
If your gynecomastia is fat or pseudo gynecomastia it will have no effect. If your glandular gynecomastia is due to pubertal changes over a couple of years ago and your estrogen levels are not high then it is also less likely to be successful at reducing or resolving the gynecomastia.
If you have not had hormone pathology you do not know if your estrogen level is an issue or not to start with, so you do not know if it would work even if you have glandular gynecomastia developed with the last few years.
For this reason you have no idea in self medicating what you getting yourslelf into.
Also, if you lower the effects of estrogens too much by taking too much Tamoxifen or similar SERM medication then you will suffer from fatigue/lethargy, your libido will be reduced and you may have difficulties attaining and sustaining an erection. Added to that you may throw your thyroid function out and that would have effects upon your metabolism.
As for liquifen. It depends upon the ingredients, which I can tell you for a fact will not have been studied at all.
Don't mess around, see an endocrinologist if your bothered about your gynecomastia.
If you post your pics people can give you there opinion as to how bad your gynecomastia is and what type it looks to be. Something that might be of consideration when thinking about going to see an endocrinologist regarding the problem.
Nolvadex is the brand name for Tamoxifen.
Tamoxifen is used to lower the effects of estrogens, by replacing the potent estrogen estradiol with a weaker/less potent estrogen at the estrogen receptor site.